100

Bahia Blanca

1832 Septemb:

Fish 390 Caught on a sand bank in the net:— body silvery: dorsal scales iridescent with green & copper; head greenish: tail yellow.

Fish 391 (a) Body pale, darker above; broard silvery band on sides; common:—

Fish 392 Body mottled with silver & green; dorsal & caudal fins lead colour: common

Fish 393 Back coloured like Labrador feldspar; iris coppery: plentiful

Fish 394 Above dirty reddish brown; beneath faint blue; iris yellow: plentiful

Fish 395 Above pale purplish brown, with rounded darker markings:—

Agama? 397 Copied

This is the most beautiful lizard I have ever seen: back with three rows of regular oblong marks of a rich brown: the other scales symetrically coloured either ash or light brown.— many also irregularly bright emerald green.— beneath pearly with semilunar marks of brilliant orange on throat.—

Buccinum 412 Copied Crawling in rushes on the sand banks & living on dead fish.— foot oblong, rounded anteriorly, the yellow operculum is placed obliquely on the upper part of extremity.— siphon lead colour, not closed; tentacula same colour pointed; mouth projecting over foot & between tentacula, when closed with small longitudinal division; from this there can be protruded a very long red coloured proboscis. terminal orifice with cartilaginous rim.— Very commonly on the whorls there are several ovules.— these are about 1/12" in diameter, (b) rounded, conical, with broarder base, semitransparent, on the summit is a circular lid, which falls

101

Bahia Blanca

1832 Septemb:

Buccinum off when the little shell is ready to obtain independent life.— At first the capsules only contain a pulpy yellow matter.— but when further advanced the minute animal: the outline of the shell is rounded oval, whorls not produced, the siphon not developed; but at the superior right corner, where the row of spines in old specimen commences, the edge of shell projects & is tranchant: animal after few minutes could crawl well; foot very large, thin; folding over the shell, fleshy siphon small; mouth & tentacula forming a triangle.—

Actinia 413 Exteriorly dirty clouded yellow.— On the exterior rim are several rows, placed without order, of bluntly pointed tentacula; they have a minute orifice at extremity.— The inner ones are the largest.— They are coloured pale lead-colour:— Central orifice projecting.— Polype most widely expansible, fixed on stones.— Within the mouth is a collar with longitudinal ridges or plaits.— The whole sack or stomach is lined by delicate membranes or rather bags (which being double form thin bags) these project upwards & much folded in same manner as bud of plant.— the superior margin is thicker: The sides of polype are composed, first (exteriorly) of a thin covering of soft matter, this does not seem to extend to the adhæring surface: 2d a strong white tough case, which must act as muscular; this on the interior surface is blueish & forms numerous longitudinal narrow plates.— between these bunches of the delicate

[101v]

(a) The young shells adhere to the old one in these places the spines are absent.─

102

Bahia Blanca

1832 Sept:

Actinia membrane is attached.— It is probable by these plates the tentacula communicate with the body.— I may mention these hasty observations as they show how singularly close the Actiniæ are in their organization to the Caryophillia as described at Page (10).

Crepidula (a) 429 Copied Adhering to the anchor, soundings 10 fathoms: shell with concave curved grooved spines: animal with foot rounded, posterior half lying on the diaphragms of shell.— Tentacula pointed with minute black eyes situated near the base & on them: mouth between them the mouth opens on each side there being a rounded lobe, having a forked like appearance. Within mouth is very short proboscis.—

Neck long.— On each side there is a membrane which when animal contracts itself closes the respiratory orifice: Branchiæ long, delicate, most regular, parallel, forming together apparently a rounded membrane — this adheres to the superior mantle by a longitudinal line.— The opening extends whole width of the shell.— From the appearance of fæces the anus must be on the right side:—

(429) There is another smaller & smooth species.— in this the foot anteriorly is crescent shaped with a horn at each corner:— also in some there on the right side near behind tentaculum was a long vermiform, tapering, generative organ.—

[102v]

(a) In sandy hillocks near the sea.─

(b) If, as I afterwards give reasons, the peduncles & branches may be considered as the same, then the Coralline will be both bi & tripinnate.—

(c) This is by far the most general, but not universal case.—

103

Bahia Blanca

1832 Octob:

Dipus: (Gme:) (777 not spirits) (a) Copied This little animal does not appear to agree exactly with any of the subgenera of Cuvier.— It was caught Octob. 3d at Monte Hermoso in B. Blanca.— In bringing at night a bush for fire wood, it ran out with its tail singed.— So that probably it inhabits bushes:— it could not run very fast: it is a male: after skinning the head it has a much more elongated appearance than it had in Nature.—

Clytia 437: 438 (b) Coralline, with branches long, fine, colourless: bipinnate; polype either terminal or at the bifurcations, scattered; Polype in cups, which are of regular funnel-shaped enlargements of the tube or branch.—  each cup has a peduncle formed of elongated globular joints.— Those which arise at the bifurcations have 5 of these, of which the three basal ones are the largest: as the Coralline grows, the peduncle becomes a branch, being lengthened between 3 & 4th joint so that the terminal cups have but two articulations, but at the base of the branch there are three. These are rather (c) from the thickening of branch are compressed, & may be considered as resulting from the form impressed on the branch when a peduncle.— Hence the Coralline appears is jointed, & at every bifurcation there are the three compressed globular articulations.— From this it would appear that the peduncle of the Clytia is really only the first form of the branch.— The peduncle is rather longer than the

104

Bahia Blanca

1832 Octob:

Clytia cup.— The central organized matter much developed included in a thin tube within the branches.— The polype unite at their bases with this.— polype when retracted have a narrow base, like footstalk; tentacula arms short, 16 (?) in number situated round a central protruding mouth.—

Plate 7, Fig 1 is a drawing of a polype retracted in its cup, with the peduncle rising at a joint in a branch.— This coralline ought to form a distinct subgenus from Clytia of (Lamouroux), the latter having the peduncle twisted, & branches not jointed, & generally short creeping.— This would appear from structure of Coralline to be more closely allied (as Cuvier ranks it) to the Tubularia than to the Sertulariæ.— I never saw anything more beautifully luminous than this Coralline was; when rubbed in the dark every fibre might be traced by the blue light.— What was remarkable <was> that the light came in flashes, which appeared regularly to proceed up the branches: The coralline emitted a strong disagreeable odour.— Was brought from the bottom in abundance in 10 fathom water.— October 1st.—

Ova Sept 29th.— The sea contained great numbers of these: as the included animal bore a great resemblance to that described at Page (2 & 73), I keep these notes: it only differed from the ova in that animal by the much greater size & having a pulsating

[104v]

(a) The part of sphere which contained the most developed granular matter projected beyond the outline of the rest:—

(b) The tail is first liberated from the contact of the inner sphere:—

105

Bahia Blanca

1832 Octob:

Ova organ at the anterior extremity: Ova spherical about 1/14in in diameter: they were in different states according to their ages. When least developed (& in this state they all were two days previously) they consist in a smaller sphere containing (a) granular matter included in a larger: this matter gradually collects in a linear direction, & the next appearance presented is a projecting rim extending round 3/4 of the inner sphere, in which is a delicate vessel & one extremity, the anterior, much largest:— When the age is much more advanced, the inner sphere is pushed on one side & a small animal lies in curved position within the outer one.— it possessed the same jumping motion as animal (of Page 2). At the anterior extremity. near the head, a heart (b) might be seen pulsating.— a central vessel was very distinct, & round on side of the tail was a fine membrane which I imagine to be the ciliæ.— All the ova contained an air globule & in consequence floated on the surface of the water:— The largest ova which I extracted or saw in the body of animal (Page 75) were only 1/50 in in diameter; if I had any reason to suppose they would increase so much in size, I should not have the slightest doubt of this being the animal; indeed I have not much now: It is very remarkable that in the extricated ova I mention a small transparent included globule.— Is not this the air globule of the larger ones?—

[105v]

(a) Not by any means universally so: sometimes the folds are for their whole length placed alternately with respect to each other.—

106

Bahia Blanca; N. Patagonia

1832 Octob 17th:

Virgularia 401 This animal is Found in the greatest numbers buried vertically in a flat of muddy sand which is left uncovered at low water.— Their superior extremities projected upwards from one to 6 inches above the sand; The whole ground is surface was scattered over with them. [several words illeg] In length they vary (& in diameter in proportion) from about 8 inches to 2 feet. Colour yellow-orange.— When touched & especially if pulled they suddenly retract their bodies so entirely or nearly to disappear in the sand. This they do with so much force that the stony axis will break, before they can by force be dragged far out of the sand.— The superior extremity is truncate, with the axis uncovered, the other extremity terminates by a soft fleshy vermiform process of a greater thickness than rest of the body stem. This lowest part lies in a curved position buried in the sand.─ A section of the axis stem is rounded, oblong, surrounding it are double two rows of oblique fleshy folds bearing the polypi.— (a) These rise at one of the narrow sides of axis, & are then opposite & apart. From this point each fold winds obliquely downwards half round the stem, where, at the opposite edge to its origin it alternately crosses with the one from the other side. — Hence at one edge there is a clear channel running down the stem.— These fillets or folds are exceedingly numerous. as they descend they become narrower & finer in proportion, at last they run into a point. here of course the opposite folds instead of meeting & interweaving on one side & nearly touching on the

[106v]

(a) The arms when collapsed form a cone, they are never withdrawn (like in Sertularia), but the papillæ on the surface are.— when fully expanded the arms are nearly horizontal like spokes of a wheel.—

(b) In this case the Polype are fewer in number. Can there be two species? Those in the bottle (401) were taken first, & were generally much longer than those floating loose in the great bottle jar ( ).

(c) It is only in the dried specimens that these project outwards.─

107

Bahia Blanca

1832

Virgularia other they are widely apart.— The place of termination is some way above the vermiform process & is generally marked by the stem being rather enlarged.— These folds are composed by the junction of numerous polypi, side by side. — When animals alive & in the water, the folds are fringed by the widely expanded & plumar arms of the polype, & stand up at large angle with the stem. (a) On being touched they fold [several words illeg] & the arms are folded together into a cone. The Each fold as it laps obliquely downwards becomes narrower.— Polype with elongated oval body united laterally, from base from the base of each a vessel runs through the supporting fillet.— These & not body of polype vary in length as the fold winds round the stem.— Arms 8 in number, not tapering at extremities, with central vessel, covered irregularly & mostly at ends with delicate short retractile tentacula or papillæ; these arms surround a mouth with lips.— The polype vary in number; sometimes being as many perhaps as 40 on one fold.— The folds are supported by hard pointed transparent spines which passing through the base are free at their upper half:— They look like which may be compared to the Calyx to a flower: they are not attached to stony axis: they are often 7 in number; but this is not constant, sometimes there being 10.— They can be applied close to the stem; but will can not diverge form at a greater angle with from it than do the

[107v]

(a) The rays have quite a crystalline fracture.

108

Bahia Blanca

1832

Virgularia Polype do when fully expanded (C)—

The stem is terminates [2 words illeg] bluntly pointed in vermiform process.— is of larger diameter than the rest of the stem.— Within this process there are two large triangular cavities, separated by a division or septum.— These cavities or channels run up the whole stem, but in the upper parts are obscure & small.— Just above the vermiform process [illeg] they are larger & filled with a pulpy yellow matter.— Within one of the 2 cavities, as will presently be mentioned, the stony axis floats:— At the point the where the polypiferous folds commence, the cavities channels become smaller & the stony axis soon becomes attached to the septum & hence is central.—a the line joining the 2 channels or cavities is at right angles to that of the opposite folds : [sketch] In the cylindrical soft part of [sketch] stem beneath the polypi, section gives first a covering of tough substance; within this & filling up the whole excepting the cavities, the substance is striated from the centre, & is composed of longitudinal of the stem shows a number of plates radiating from the centre: in the parts of stem where the folds polypi are fully developed this structure nearly disappears, & it is through this they first The [illeg] consists of a white softer substance.— (like to the marrow in bones!). The external part [illeg] white semi-opake; superior  extremity abruptly truncate, figure rounded oblong; at the narrower end there is a slight

[108v]

(a) The circulation was strongest at the very bend; it was irregular

109

Bahia Blanca

1832

Virgularia D depression or channell, & it is along these that the cavities within the stem run. —

The axis gradually tapers from its upper end to the finest point at the lower end.— at this & At the lower end, the extremity is suddenly curved backwards. Here the axis consists of a dark line centre part enveloped in a transparent covering, afterward doubtless forming which no doubt is connected with the exterior white stony part layer.— This recurved part of axis is included within a capacious membranous transparent elastic (irritable?) bag, which some way above the bend contracts round the axis & is probably continued all up the stem together with it in close apposition to the stony axis.— The lower part of the stony axis lies loose in one of the cavities, but in the higher parts where the polypi are stand, it is imbedded in or chiefly forms the septum between the two channels.— it is attached at the corners of the polypiferous folds to the enveloping fleshy parts, & I think it probable that the vessels from the polypi lead into the membranous case of axis (?) :

In the elastic terminal bag, which encloses the terminal & recurved parts of the stony axis, there was a most distinct but irregular circulation of a fluid containing particles; this was even visible when the axis was entirely removed out of the body.— The circulation of the particles was strongest & most [3 words illeg] at the point where the axis was most bent. The axis evidently performs a very essential part in the economy of the animal; it is by this that the whole stem is kept in a vertical position & that the upper part stands upright in the water, & so allowing many of the polype to have free access to the surrounding medium fluid.— When a bit of the stem is cut off, the axis projects at each both extremities; & this shows the high contractility of the softer parts of

110

Bahia Blanca

1832

Virgularia the stem.— Hence By this power the animal whole stem its body is easily withdrawn into the sand; but at first sight its manner of rising again is not so clear: upon considering the erratic nature of the axis, its inferior extremity floating loose in a cavity, & the lower part of this cavity lying in a curved position, it is clear that when the animal retracts itself, the axis must, from being forced into the terminal vermiform process, exert from its bent shape a considerable force; So that as soon as the animal ceases to contract itself, the stem would gradually rise:— But (As it appears improbable that the polypi in so large a part of the lower end of the stem should be buried in the sand.— perhaps hence when in deep water the tide rises I suppose that nearly the whole body stem is protruded. A very small force would be sufficient to enable the animal to work its way back again withdraw into the soft sand, for the spines under the folds would act as pauls.— but in this case I do not exactly see how the animal works upwards stem could protrude to so great a distance, as the elasticity of the axis would not in this case come into play ?).— (In the vermiform process, at the very extremity I found several ova, in shape regular oval; they contained granular matter; was of an orange colour; & a length 1/1000 of inch.— I think they had only just been formed; this being the early part of Spring renders this the more probable; when I having examined some specimens a few weeks before I anyhow did not then observe them any.— Above the vermiform process, the 2 internal channels or cavities were for some length filled [illeg] with yellow pulpy matter.— This examined under a simple microscope

[110v]

(a) Does not the great size entirely separate this fact from the "Molecular movement" of Browne?

(a) The motion continued for some time in distinct particles (as long as I watched them) when kept in water.—

111

Bahia Blanca

1832

Virgularia presented an extraordinary appearance.— The Mass consisted of various shape sizes of irregular globular semi-transparent particles; the larger ones being merely an aggregation of the smaller ones. All these grains possessed a most distinct very rapid vibratory motion, generally round varying axis'es, but sometimes progressive.— The motion continued for a long time, as long as I watched it. I first saw it with a simple lens of 1/3 of inch focal distance, but it would have been quite clear with a less power; I accurately examined the particles with a strong light & 1/20 focal distance.— It seems probable that these particles go towards forming the ova & that when ready for expulsion when formed they pass through are pulled along the 2 longitudinal cavities channels to the upper part leading into the open sea.—

In this respect the animal (if my memory is correct) differs from the Virgularia mirabilis which I saw examined in Edinburgh [illeg]; for in this species the ova were scattered in the fleshy part between the polypeferous folds.— (Were they then passing through an internal vessel?? ).— The above movement in the particles was more rapid & I think quite distinct from that of the particles in the elastic bag [illeg] to lateral part of the [illeg] .— the latter would seem to bear some obscure analogy to a true circulation.— I have called this animal Virgularia; but it [illeg] seems to form a new genus: it is most allied to Virg: juncea, but widely different in form of axis & in spines.— According Cuvier, the occurrence of spines being the leading character, it would be a Pennatula, from which genus it differs still more widely in habits & general appearance. —

[111v]

1833 Summer

(a) Mr King tells me, that when in the Schooners on the coast of Patagonia, he & the others several times saw Ostriches swimming from one island to another.— This occurred at the Bay of San Blas, & at Port Valdes.— They took to the water when driven, & likewise of their own accord without being frightened.— The distance in both places about 200 yards.— When swimming very little of their bodies appears above water & their neck is stretched forewards, as a Goose or Duck in flying.— Their progress is slow.— Before hearing this account, everyone was surprised to hear of the plenty of ostriches & Guanacoes in the various small islands of San Blas.— The latter animals were often seen swimming.—

December. The male ostriches are easily distinguished by the Gauchos from the female, by the greater size of head & body & colour.— It is a most undoubted fact that the males sit on the eggs: the females never.— As the number of eggs in the belly & the nest seem to correspond, 20 to 40 or 50.— it would seem hard to be ascertained, but I was assured 4 or 5 females have been watched to lay their eggs one after the other in same nest, in middle of the day.— The reason seems obvious — if a female were to deposit 40 eggs successively one after the other, & then sit on them. The first would be so many days older than the last laid egg.— The same cause explains the male sitting, because it must more very often happen that the female has not ceased laying.— The male will not rise from the nest, without you pass very close.— They sometimes are dangerous; attacking, kicking, & trying to jump upon the horse.— My informer had seen an old man much terrified by one chacing him.— The eggs which I have called Watchos are supposed (Turn over)

112

Bahia Blanca

1832 Octob:

Struthio rhea (a) (b) 814 (not spirits) Cop

This bird is very common in the sandy plains: in its stomach I have found roots of vegetables: at low (a) water they come down 3 or 4 together to the sand bank, the Gauchos say for small fish; in their (b) habits shy & wary, generally solitary; emit a very deep note: During September & Octob. we found an extraordinary number of eggs, in colour varying from pale yellow to white: the male eggs weight the most (am told so).— The eggs are either found scattered about, when they are called Watchos, or collected in circular shallow excavations or nest.— Out of the four which I saw, 3 contained 22 eggs each; & the other 27:— In one days hunting 64 were found; 44 of these were in two nests — the other 20 scattered about.— It seems strange that so many of the latter should be produced for no end, as Cuvier mentions the Gauchos state that many females lay in the same depository & that one male sits on them.— I can scarcely credit this; anyhow it is clear from the number of eggs that each female lays many eggs, & in the oviduct (it was told me by those who cut one up for the ships company) that there was nearly 50, of a regular gradation in size.—

Cavia patagonica Copy 817 (not spirits) Frequent in the sandy plains, feeding by day; Azara states that they only frequent the holes of the Viscaches, & that only when pressed by hunting (Griff: animal k:4).

[in margin] Found near Mendoza Traversia to the South

They certainly wander far from any holes; but they abound like rabbits in a warren, where there is a collection of holes.— I have watched them sitting on their haunches by the mouth of a burrow, which they will enter immediately they are frightened.— The dung is

[112v]

(a) I must except Trox.— This I observed also at M: Video.

Ostrich (b) by the Gauchos to be laid first.— Perhaps before association [illeg] to the Male. The ostrich, with a its swiftness, is easily balled, for they are simple animals & are easily turned & puzzled.— They generally run against the wind.— In fine weather, they will try to conceal themselves amongst the long rushes, & will thus lie till closely approached.— The noise of the ostrich (male I believe) is like a deep drawn breath.— it is neither easy to say where it comes from, or how far distant is the animal which makes it.— The first time I heard it, I thought it was a Lion or other wild beast.

Wallis saw Ostriches in Bachelor river in the Stts of Magellan, Lat between 53° and 54°.— When at the R. Negro, I heard much concerning the "Avestruz petises", a species of ostrich ½ the size of the common one.— The following I believe to be a tolerably accurate description, colour mottled, shape of head, neck, body same as in ostrich.— legs rather shorter, feathered to the claws; feathers same structure as in ostrich; hairs about the head.— cannot fly, is taken more easily than other ostrich with the balls.— This bird is however more universally known by its eggs, which are little inferior in size to the Rhea, but of a blue green colour. It generally frequent near the sea, frequently to the South of R. Negro, San Josè, & I believe near the Colorado, but not further Northward.— V 212 more particulars.— The Northern Gauchos know nothing about the Avestruz Petise, even at Bahia Blanca. Albino varieties of the common Ostrich have been seen; it must be a most beautiful bird.— snow white, Gaucho at R. Negro told me.

113

Bahia Blanca

1832 Octob:

Cavia patagonica (z) of a remarkable shape, being an elongated regular oval.— now if the Viscaches were in sufficient numbers to dig the holes for the Agouti, some considerable quantity of dung would be lying about.— I did see some like (but smaller) an English rabbits, but I think it belong[s] to the Toco Toco, a small Rodentia which I know inhabits burrows in the same plain.— The manner in which the Agouti runs more resembles that of a Rabbit than a Hare. It consists in so many distinct springs.— The body weighs from 20 to 25 pounds.—

Lizard 454 455 Monte Hermoso.— In its depressed form & general appearance partakes of some of the characters of the Geckos.— Colours above singularly mottled, the small scales are coloured brown, white, yellowish red, & blue, all dirty, & the brown forming symetrical clouds.— Beneath white, with regular spots of brown on the belly.— Habits singular, lives on the beach, on the dry sand some way from the vegetation.— Colour of body much resembles that of the sand.— When frightened, it depresses its body & stretching out its legs & closing its eye tries to avoid being seen; if pursued will bury itself with great quickness in the sand.— legs rather short: it cannot run very fast.—

Hybernation of Animals Sept: 7th.

Upon our first arriving here, Nature seemed not to have granted any living animals to this sandy country.— By digging in the ground I found several Carabidous & Heteromerous insects, Mygalus & some species of Lizards, all in

[113v]

NB. For the future, the marginal letters will refer to notes on the back of page.—

(z) This animal is the most common characteristic animal of the dry plains of [illeg] Patagonia: It does not occur to the North of the Sierra Tapalguen 37°.30′.— our officers have never seen it to the South of Port Desire 47°.— The Gauchos are of different opinions respecting its digging holes.— I have no doubt it uses them Biscatche holes where they occur, but I think certainly it must be its own workman in those parts where the Biscatche is not common, as S. part of Patagonia where I do not believe Biscatche is found as the little owls do, which in B. Oriental are obliged to make for themselves: Two tolerably fast dogs often run them down.— Their flesh is very white & pretty good.— They bring forth two young ones in their holes.— Southern limits between Port Desire & St Julian (48°:30'). The Gauchos at B. Blanca say certainly that it digs its own holes.—

114

Bahia Blanca

1832

Hybernation a half torpid state. On the 15th different animals began to appear & by the 18th everything announced the commencement of Spring.— The plains were ornamented with flowers (a); birds were laying their eggs; numbers of Heteromerous & Scarabidous1 insects were crawling about. The Saurian tribe, the usual inhabitant of a sandy district, were darting in every direction. For the first eleven day, from the 7th to 17th (both inclusive) the mean temperature from bihoral observations at 2 hours interval was 51°.3.— & I see that generally in the middle of day thermometer was from 52° to 55°.— In the 11 subsequent days, in which Nature became so animated, the mean was 58°.1.— Thus giving a difference of nearly 7°.— the general range of Temp: in middle was even in [illeg] greater than this, varying from 60° to 70°.—

At M: Video, every animal was hybernating (Vide P 120) when the mean Temp: was 58°.4 & in the day Therm: often rising to 70°.—

The difference of Latitude between the latter & this place is four degrees or 240 miles; Thus showing how much the general annual Temp: affects the degree at which animals reassume their living process.—

Entomology By far the most abundant order is Coleopterous: In this Heterom & Lamellicorn were in numbers of individuals by far the most prevalent. in species the first contained about 10, the latter 9.—

[114v]

(a) Such as Parrots, Swallows, Hawks, Partridges: Ostriches were laying when we first arrived:—

115

Bahia Blanca

1832

Entomology Amongst the Carabidous (or more properly Harpalidous) there were 7 distinct species: but all very rare.— in my collection I have every individual I have seen6.— The other Coleopterous insects make no figure. I found one Staphylinus, Colymbetes, 2 Crysomela, Elater, 2 Coccinella.— Amongst the Diptera Musca was abundant & a Bombylius.—

The orders Orthoptera, Hemiptera, Neuroptera, produced scarcely anything.—

Vide Collection (a) In Hymenoptera, a large Pompilus was common, as was its prey Mygalus:— also a large humble bee feeding on the wild pea.— I saw three species of Lepidop: diurniæ: the Nocturnæ were more abundant.—

Entomostraces (Lophyropes) (b) 457 (c) This animal does not come in any of Latreilles families.— In general appearance most closely resembles Ostracodes; but in structure very different.— Shell bivalve, gaping at each end from the approximation of the central parts of lower edges.— Back round curved, posterior extremity rather pointed, the other rounded: The animal could not completely close the anterior & posterior longitudinal orifices: Eyes 2 pedunculated, formed of a transparent substance enveloping dark central mass; their eyes were in constant motion. Between & beneath there were two antennæ, & in their structure most singular. Peduncle thick strong, nearly the length of the shell [3 words illeg]— terminated by a large circular transparent sucker; on the internal edge, there was a small branch with setæ, & on the posterior a bunch of Setæ.— the

[115v]

(a) Ants are very common: on Sept 22d Swarms were on the wing.—

(b) It did not occur to me at first that by counting the rudimentary legs there will be 24, & that in its other characters (2 pediculated eyes, flat calcated legs &c), it must belong to the division Phyllopes.— Eggs in this one were irregular, numerous in the dorsal posterior part of shell.—

(c) Octob: Examined another specimen.— Each of the 12 legs is bisected at its summit, from whence proceeds a bunch of setæ.— this is more true than saying a small external leg: Eyes are formed of number (not many) some small transparent globules, seated on a dark coloured pedunculated mass. The body attached to the dorsal part of shell by many parallel tubes or vessels: these perhaps act as Branchiæ.— Mouth obscure, with two curved pointed jaws (mandibulæ or maxillæ) united at base & forming a horse shoe.— ((⸮) At base of Antennæ there are 2 rudimentary palpi (?):) Shell has not a true dorsal hinge, but merely a line: shell very tough elastic, with numerous fine parallel vessels running in it.— The jaws resembled the mandibuliform horns of Branchippus10 figured in Desmarets:

Decem 2d  Lat 40°.20′ S. Coast of Pat.

The posterior part of body was to certain extent divided by lines into 6 segments, which corresponded with the 6 prs of legs: does this now show that this number is normal & that the bisection of legs at summit ought not to make the number 24.— Animal not uncommon in open ocean: I find my description very accurate; perhaps the antennæ are obscurely jointed: tail very small:—

116

Bahia Blanca

1832 Octob 23d

Entomostraces (Lophyropes) whole organ instantly reminded me of the front leg of male Dyticus, only that in the latter the Tarsi (answering to the joint with setæ) incline outwards.— The cups or plates adhæred firmly to glass or any other object: it was most curious to then see the animal walk; this it managed very deliberately with with long strides, the swimming legs helping to keep the lower edge of shell vertical.— Thus it walked up the side of a watch glass; but from the inclination, the shell often fell over & by so crossing the leg-like antennæ interfered with its motions.— The mouth is obscure, & is seated at base of Antenna, within the central parts of anterior half of shell.— The body seems to be attached anterior half of shell, & the stomach &c lies above & behind the head, the posterior half of body is free: so as to be more or less drawn up, it is terminated by short simple jointed tails, with double bunch of few setæ.— It & legs are protruded by the posterior opening.— 6 pair of similar equal natatory legs; base jointed, with flat row of setæ ; (acting like caudal swimming in the "Macrourus") each one formed of row of strong setæ, on jointed base; At origin of leg is a small projecting point, or rudimentary leg, with few bristles:— there were no branchial plates.— Animal could swim laterally very rapidly, generally in circular direction; antennæ retracted: Shell hard elastic.— Animal coloured blue; in open ocean South of Corrientes.—

[116v]

(a) There is no separation between head & thorax or body.