(B

Abstract

Caps of tin-foil when extended down the cotyled for a length of bet .15 & .2 of inch from the apex were placed at different times on 20 cotyledons & a seedling from 6° 30 7° 45' which were exposed to the light— other seedling bowed in Pots — Height of seedlings — how the result of this [illeg] of the summit being protected from light was.

p.4. 1 2 3 4} Dark Caps .15— to .2 (6° 45) vertical do do do

Second Abstract

p 5B (5) .19 6° (7°.45') p 5C. (6) .2 (7.40') do (7) .19 do (8) .19 do (9) .13 (say .15) p. 6 (10) .2 (7°30') — (11) .17 (12) .2 .18 (13) .2          (14) .2 p. 5.A omit (15) .15 (6°30')          (16) .15 p 8. (C) (17) .19 (7°40') do. (18) .2 ─ ─ p 8. (19) .2 — (21) .25 deep quite vertical (20) .18 (22) .25— slightly curved to Light — It shd be remembered that all the [illeg] plan All plants in Pots 1/3 to 1/5 of plants see diagm add the 2 anomalies.— (so contrast great)

Height of Plants vertical — .9 in Height vertical 1.15. high vertical .8 high vertical 1.1 high vertical .9 high vertical vertical vertical — but bent transversely vertical vertical vertical vertical} about .4 of inch very slightly curved to light 1.05 high slightly curved, but remained curved all night curvature increased during night omit {vertical in relation to light, but greatly bent transversely & remain so all night slightly curved to Light & much rectangularly turning transversely — pipe not well closed at base First (6 of the vertical ones tested by exposing for same length of time aft pipe reverse & become greatly curved.)

Two other cases were in in which caps of unusual depth. viz .25 of an inch though not in comparable in degree with the unprotected seedlings in the same pot were used & both became very slightly curved towards light. These caps were heavier than usual, but whether this is the explanation I do not know. In 2 other cases the caps were certainly so much too heavy, that for the Cots. had no power of straightening themselves at night.

p. 6 (23) Pl. .95 high cap .25 slightly curved & then became straight. Plant .95 high

(24) cap .2 deep— very considerably curved & remained as much curved as any during night

64

Chap. 17 18 Mammals – Colour.

the sexes of which cannot be distinguished by colour, even by the dealers in wild beasts. Mr. Wallace believes 38*(56) that the vertical his striped coat "so assimilates the vertical stems of the bamboo, as to assist greatly in concealing him from his approaching prey." But I am not satisfied with this view; for look at the striped zebra, an inhabitant this view does not appear seem to me satisfactory. The zebra is conspicuously striped even more even, & on of the open plains of S. Africa cannot be thus protected. Burchell 39*(57) says, after passing in passing of by a herd of these animals, "their clear sleek ribs glistened in the sun, and the brightness and regularity of their striped coats, presented a picture of extraordinary beauty, in which probably they are not surpassed by any other quadruped." In the case of the tiger we have some slight evidence (leading us to suspect that his beauty may be due to sexual selection, for in two other species of Felis the analogous marks & colours and markings are rather more brighter in the male than in the female, but With the zebra, on the other hand we have not even this kind of slight evidence,) as throughout the whole group of the Equidæ the two sexes are identical in colour. Nevertheless he who attributes to sexual selection the white and dark vertical stripes on the flanks of several kinds of various antelopes, whether or not equally displayed in the two both sexes, will probably extend the same view to the Royal Tiger and beautiful zebra.

[Descent 2: 302: "The same conclusion may perhaps be extended to the tiger, one of the most beautiful animals in the world, the sexes of which cannot be distinguished by colour, even by the dealers in wild beasts. Mr. Wallace believes38 that the striped coat of the tiger "so assimilates with the vertical stems of the bamboo, as to assist greatly in concealing him from his approaching prey." But this view does not appear to me satisfactory. We have some slight evidence that his beauty may be due to sexual selection, for in two species of Felis analogous marks and colours are rather brighter in the male than in the female. The zebra is conspicuously striped, and stripes on the open plains of South Africa cannot afford any protection. Burchell39 in describing a herd says, "their sleek ribs glistened in the sun, and the brightness and regularity of their striped coats presented a picture of extraordinary beauty, in which probably they are not surpassed by any other quadruped." Here we have no evidence of sexual selection, as throughout the whole group of the Equidæ the sexes are identical in colour. Nevertheless he who attributes the white and dark vertical stripes on the flanks of various antelopes to sexual selection, will probably extend the same view to the Royal Tiger and beautiful Zebra."]

(C

Caps. of less depth longer than .05 & than .15 of inch

many of them generally about a tenth of a inch between .06 & .1 in depth

Second Abstract

(6.30') p. 5A (1) .1 vertical X — — (2) .08 vertical X — — (3) .07 slightly curved to light (2 of these greatly curved when caps removed) p 5 (C) (7°. 40') (4) .1 slightly curved to light (5) .1 slightly curved (6) .06          very considerably curved to L. (7) .12          slightly curved, (but rather obliquely with respect to light & so remained all night) (8) .1 somewhat curved to light

Height .4 of inch. do only .31     1 inch high 1.05. do .8

Of the 2 vertical. — 5 slightly curved — increasing much less than other seedlings in pot — 1 alone considerably curved. Here again more seedling in the other same pots been greatly curved,

By comparing this table with the last, we see that it is the sensitive part

(Another trial was made in d different manner, viz by bandaging with a strips of the the blackened tin foil, about .2 in breadth (with [illeg] filled up with black Indian ink ) the summit of some cotyledons a little over 1/2 inch about .6 in height. Thus ; so that The tips itself & the whole basal part, were then left fully exposed to a lateral light during 8 hours. The seedlings were about .6 in height & 4 of them then Four seedlings had their tips for a length of .05 exposed, & then the tips then of 2 of these become slightly curved to the light, while the whole curved base part stood remained remained quite vertically; two became quite upright excluding the tips itself which 2 other 2 seedling became very slightly curved toward the light for the whole length. The tips of Two other seedlings had their tip were left exposed for a length of .04 exposed ; one of these remained almost vertical & the [illeg] other 3 became considerably inclined to the light. All The other many f free seedlings in the same pots all all became greatly curved towards the light.)

With respect to the trial with blackened extremely thin glass tube, this was at first coated in Ind. Ink

(63A

Chap. 17 18 Mammals – Colour.

It is at least inconceivable that such marks and colours (Fig) can be of any other ser service to these animals. For for instance, both sexes of the Koodoo (see Fig 62) (Strepsiceros Kudu) have on their hinder flanks narrow white vertical lines, & with on their forehead an elegant angular white mark. Both sexes in the genus Damalis are very oddly coloured; and in D. pygarga the back and neck are purplish-red, shading on the flancks into black, which is abruptly sp separated from the white belly, legs and a large white space on the buttocks above the base of the tail; The head is still more oddly coloured, a large oblong white mark, narrowly edged with black, covers the face up to the eyes; (Fig. 69) there are three white stripes on the forehead, and the ears are marked with white. The fawns of the species are of a uniform are pale yellowish-brown. In Damalis albifrons the head differs in there being only a single white stripe replacing the three stripes on the ears are being almost wholly white 37*(55). After having studied to the best of ability the sexual differences of animals of belonging to all classes, I cannot avoid the conclusion that the curiously arranged colours in of many antelopes, though common to both sexes, are the results of sexual selection, primarily applied to the male.) & transferred to both sexes the females.)

What shall be we say about (The same conclusion may perhaps be extended to namely the tiger, one of the most beautiful animals in the world, of which

[Descent 2: 300-302: "It is inconceivable that such colours and marks can be of any direct or ordinary service to these animals; and as they have almost certainly been intensified through sexual selection, it is probable that they were originally gained through this same process, and then partially transferred to the females. If this view be admitted, there can be little doubt that the equally singular colours and marks of many other antelopes, though common to both sexes, have been gained and transmitted in a like manner. Both sexes, for instance, of the Koodoo (Strepsiceros Kudu, fig. 62) have narrow white vertical lines on their hinder flanks, and an elegant angular white mark on their foreheads. Both sexes in the genus Damalis are very oddly coloured; in D. pygarga the back and neck are purplish-red, shading on the flanks into black, and abruptly separated from the white belly and a large white space on the buttocks; the head is still more oddly coloured, a large oblong white mask, narrowly-edged with black, covers the face up to the eyes (fig. 69); there are three white stripes on the forehead, and the ears are marked with white. The fawns of this species are of a uniform pale yellow ish-brown. In Damalis albifrons the colouring of the head differs from that in the last species in a single white stripe replacing the three stripes, and in the ears being almost wholly white.37 After having studied to the best of my ability the sexual differences of animals belonging to all classes, I cannot avoid the conclusion that the curiously-arranged colours of many antelopes, though common to both sexes, are the result of sexual selection primarily applied to the male. The same conclusion may perhaps be extended to the tiger, one of the most beautiful animals in the world, the sexes of which cannot be distinguished by colour, even by the dealers in wild beasts.
37 See the fine plates in A. Smith's 'Zoology of S. Africa,' and Dr. Gray's 'Gleanings from the Menagerie of Knowsley.'"]