RECORD: Darwin, C. R. [1874].07.25. Utricularia. CUL-DAR59.1.161-162. Edited by John van Wyhe (Darwin Online, http://darwin-online.org.uk/)

REVISION HISTORY: Transcribed by Christine Chua and edited by John van Wyhe 10.2022. RN1

NOTE: See record in the Darwin Online manuscript catalogue, enter its Identifier here. Reproduced with permission of the Syndics of Cambridge University Library and William Huxley Darwin. The volumes CUL-DAR 54-61 contain material for Darwin's book Insectivorous plants (1875).

Utricularia is a genus of carnivorous plants known as bladderworts. These notes are for Darwin, C. R. 1875. Insectivorous plants. London: John Murray. (F1217)


[161]

Utricularia— Cheshire July 256 th (U minor)

The first Bladder which I opened contained 24!! Entomostraca in all state of decay some containing only a few globules of red oil — various species, apparently different & smaller than those in U. vulgaris— The bladder before it was opened, seemed all surrounded on edges with yellowish-brown decayed matter.

Valve transparent opens inwards

Spines on valves & glands & glands on margin [sketch] — antenna

Valves much squarer than in U. vulgaris.

(Another bladder had 20 Entomostraca in it.)

(Another small bladder with 15. do.)

Bristles at anterior end on side of margin of valve & bristle at right angles on outer side? of antennae (Another 10 Entomostraca several larger)

(Another bladder 7, but then 5 of these large, seemed stuffed full.

[161v]

[sketch] A opened out

[sketch] former valve Tips of These bifid tips to what I suppose are leaves form?? I suppose the animal??

I suppose base of leaf broadened & edges meet & cohere

If this view is correct the base of antennæ being prolongation of leaf is no argument of importance of structure. N B I have just found very young bladder, with surface apparently not yet united — like A, but edges in contact, & with bifid extremity of leaf unmistakable.

In U. vulgaris insects, especially larvæ do not appear digested, but converted into brown pulpy mass

[162]

I have just glanced at inside of bladder & can see with weak power numerous spines. much finer, I think, than in U. vulgaris, & many of them, but not all full of spheres of protoplasm. — I cannot make out that they are quadrifid, & they seem much thinner & more pointed, but power not high enough.

There was some decayed animal matter round these spines with spheres, so some just like U. vulgaris

There were 7 spheres in 1 spine, but more in others — spines seem longer & thinner than in U. vulgaris. These spheres change ⸮ their arrangement & relative position — are in movement. Nothing but Entomostraca


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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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