410 On an "Octopus '"' loith BrancJnng Arms. 



The species appears to be the Polypus cephea (Gray) * 

 described from a single animal in the British Museum. 

 Although no special mention is made by Gray of the small 

 cirri in front of the eyes, they really exist in his specimen, 

 and the round pore-like circle behind each eye is also trace- 

 able. Gray did not give the colour of his species, but it is 

 spotted just in the same way as the specimen now described. 



Upon the cause o£ the peculiar abnormality of this animal 

 I cannot venture an opinion. That it is an aberration from a 

 normal type is, I think, very evident, for were it not so we 

 should expect to find some regularity in the forking of the 

 arms. Such, however, is not the case, as neither the dorsal 

 pair, the laterals, or the vcntrals exhibit any similarity. 



With regard to the use of the generic name Pohipus of 

 Schneider, Dr. Hoyle f has shown that it must take the 

 place of the commonly accepted Octopus, but his supposition 

 that it had been overlooked by modern writers is not quite 

 the case, for Jeffreys J, in describing Octopus, observes that 

 it is " the genus Polypus of Schneider, but Leach seems to 

 be the only modern naturalist who has adopted that name." 

 This paragraph seems to have escaped Dr. Hoyle's notice, 

 for he remarks : — " Jeffreys' attribution of the genus Loligo 

 to Schneider migiit seem to indicate that he was acquainted 

 with it [Schneider's work], but on that hypothesis it is 

 difficult to explain why he quotes Sepiola as of Leach and is 

 quite silent as to the prior names for Octopus and Eledone.^^ 

 In justice to Jeffreys I may mention tliat he does 7iot quote 

 Leach as the author of Sepiola, but Rondelet. I may also 

 refer to the fact that Owen § was acquainted with Schneider's 

 work, and gave an outline of his classification, and, had the 

 " law of priority " been observed at that time, doubtless he 

 would have employed the name Polypus. Finally, I would 

 point out that Philippi, in his ' Handbuch der Conchyliologie/ 

 p. 93, published in 1853, has employed the genus Polypus, 

 Schneider, sinking Octopus as a synonym. 



* Cat. Cephalopoda Antepedia Brit. Mus. p. 15 (1849). 

 t Mem. Manchester Phil. Soc. vol. xlv. uo. 9, pp. 1-7. 

 X Brit. Couch, vol. v. p. 143. 

 § Trans. Zool. Soc. 1838, vol. ii. p. 125. 



