The Complete Work of Charles Darwin Online

RECORD: Darwin, C. R. [ny].03.23. Dr Günther showed me male & female of Plecostomus barbatus. CUL-DAR82.B13. Edited by John van Wyhe (Darwin Online, http://darwin-online.org.uk/)

REVISION HISTORY: Transcribed by Christine Chua and edited by John van Wyhe 2.2022. 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-DAR80-86 contain material for Darwin's book Descent of man (1871).

Darwin cited this in Descent 2: 10-11, n16: "See Dr. Günther on this genus, in 'Proc. Zoolog. Soc.' 1868, p. 232."

[B13]

B. Mus. Mar 23 Dr Günther shewed me male & female of plecostomus barbatus, a siluroid fish from f. water of S. America, in which the mouth of male is thickly fringed with stiff hairs homologous with the [scales] on the head. The female has a mere vestige of this beard another spec. of the same genus, in the male, has several soft, flexible tentacles

[B13v]

on the front part of the head which are absent in the female. These tentacles are prolongations of the true skin & evidently serve the same end as beard of the 1st species.

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