From C. S. Bate   24 May 1868

8, Mulgrave Place, | Plymouth.

My dear Sir

In a collection of Crustacea recently added to the British Museum—I saw a day or two since four specimens of Gelasimus from Zanzibar, all of which had the left arm the larger. When I wrote to you previously I felt a doubt on the subject1

As far as my experience goes all long & large armed crustacea are indolent & sub-burrowing creatures. May not the big claw be for the purpose of reaching far & drawing food within reach of the smaller & more directly feeding claws and to seize the female when at a distance?—2

Yours sincerely | C. Spence Bate

May 24—68

CD annotations

1.1 In … distance?— 2.4] crossed pencil
Top of letter: ‘left chelæ [interl] are larger’ blue crayon; ‘Used’ pencil
1
See letter from C. S. Bate, [17 February 1868]. In Descent 1: 330, CD wrote that Bate had informed him that the right-hand chela (pincer) was generally, though not invariably, the larger. Gelasimus (now Uca) is a genus of fiddler crabs.
2
In Descent 1: 331, CD suggested that the main use of enormously developed pincers in the male was to seize and hold the female.

Please cite as “DCP-LETT-6204,” in Ɛpsilon: The Charles Darwin Collection accessed on 5 June 2025, https://epsilon.ac.uk/view/dcp-data/letters/DCP-LETT-6204