The Complete Work of Charles Darwin Online

RECORD: Darwin, C. R. n.d. [Abstract of Owen, Memoir on pearly nautilus]. CUL-DAR205.9.139. Edited by John van Wyhe (Darwin Online, http://darwin-online.org.uk/)

REVISION HISTORY: Transcribed by Christine Chua and edited by John van Wyhe 9.2021. RN1

NOTE: The brown crayon number '22' indicates that this document was filed by Darwin in his portfolio for the subject of Palaeontology: extinction.

Reproduced with permission of the Syndics of Cambridge University Library and William Huxley Darwin. The volume CUL-DAR205.9 contains notes on palaeontology and geology [regarding theory of evolution].

[139]

Memoir on the Pearly Nautilus by R. Owen 1832.

p.31. Sepia shows affinity to Nautilus in its Laminate shell - in extremities of branchiæ being unattached & in a rudimentay accessory branchiæ - Hence Sepia closest to the tetra-branchiate & lowest form of Cephalopods. See d' Orbigny's memoir –

p. 39. Nautilus has an [inferiory] constructed brain & more simple eye, than in the dibranchiate group

p 50. Nautilus is an osculent form between cephalopods & gasteropods, (though belonging to former clearly) Pteropods do not come between. It is interesting the tetra-branchiate including Nautilus Ammonite, Belemnites Spirula (?) (Over &c & being older than the other recent genera - see Owens paper on Belemnite; does he yet Consider Belemnite as tetra-branchiate—

over

[139v]

Owen on Belemnite p. 82. It seems that in 1836 - He classed Spirula & Belemnite with the Dibranchiate Cephalopods & his first examination of Belemnite leads still further to this. Considers Belemnite as intermediate between Spirula & Sepia

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