RECORD: Darwin, C. R. 1836.08. Zoological diary: Bahia. CUL-DAR31.367-368. Edited by John van Wyhe (Darwin Online, http://darwin-online.org.uk/)

REVISION HISTORY: Transcribed by Richard Darwin Keynes in Zoology notes (2000, F1840). Revised and supplemented here by Christine Chua to correspond to the manuscript images. Edited by John van Wyhe 6-7.2022. RN1

NOTE: Original transcription reproduced with permission of Richard Darwin Keynes, the Syndics of Cambridge University Library, English Heritage (Down House Collection) and William Huxley Darwin.


367

Bahia Brazil

1836 August

Corallina 1463 Spirits 3854:55:56 This species is very common encrusting the smooth surfaces of the granitic rocks in the tidal pools.— Its colour in the under surfaces is rather paler than that of Corallina officinalis, but generally it is cream-coloured, with a tinge of flesh-red.— The extremities of the short rigid branches (in 1463) are either rounded & white or acuminated into a cone. In this latter case the summit is surmounted by a perfectly circular minute orifice, which leads by a short cylindrical tube into a circular cavity occupying the base of the cone.— [sketch] The structure of the branch shows rectangular intersections of concentric with vertical plates, & the cavity does not appear to lie conformably with these plates. — On breaking off the terminal cone, the cavity is seen to be occupied by a white mass, which from the disturbance has appears like an intestinal mass. It is found to consist of from 20-40 separate cylindrical bodies attached by the lower extremities & embedded in a pulpy matter; which they are placed in a vertical & nearly parallel position.— These occur, & in the same cavity, in several states; some consist of a simple elongated sack with a little granular matter, which presently assumes one or two obscure artic circular contractions.— But the greater number & most perfect ones are in dimensions 3/500in long & 1/500 broard; under the

368

Bahia Brazil

Corallina microscope they are seen to consist of an envelope containing full of a pale brown granular matter.

The envelope has a necklace form, owing to three ring-like contractions, partially dividing the little cylinder into four beads.— [sketch] These contractions do not appear to form true articulations, for they are far from separating the internal granular matter:— At the lower end, the terminal arti lobe has a point or navel of attached flocculent granular matter: the superior lobe is generally rather larger & more elongated than the others.— These articulate-like contractions in the most perfect bodies amounted to three, but in the less developed were two & even one; & lastly as I have said, an obscure sack can alone be distinguished in the enveloping matters.— I conceive these are the gemmules or seeds.— In one case I saw one of their cones placed on the side, but near the summit of a branch.— Many of The greater number of the terminal points extremities of the branches are white & rounded. Are these Have the cones been removed from these? I am inclined in some cases to think so, from marks of a slight depression & a scaling structure, which appear general manner of healing.— I saw in section of some branches the trace of an obliterated cavity.—

[368v]

depth ─ coral reefs ─


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Citation: John van Wyhe, ed. 2002-. The Complete Work of Charles Darwin Online. (http://darwin-online.org.uk/)

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