(wo rare British Nudibranchs. 381 



loosoncd its hold of the side of the glass vessel and progressed 

 slightly by means of these contractions. Again, after 

 floating foot u))\vard.s for some time, it would wriggle to the 

 bottom and ini mediately gain a footing. 



My s]iocimcH was quiet during tlie day. In the morning 

 I found that it had crawled out of the dish where it had been 

 placed overnight. Tiiis was done constantly, and indicates 

 nocturnal habits. During the three weeks that I kept my 

 specimen no spawn was deposited ; hence probably it was 

 immature. 



As regards the significance of these observations. Con- 

 tinual changes of form in the ])leuropodial ])apillfB during life 

 have been noticed by Dr. Norman in his species, L. Hancocki'^ . 

 The complete similarity, however, both in characteristic 

 form and power of coordinative movement possessed by these 

 papilla? in common with those of tiie "calyx-sheath " appa- 

 rently escaped him, and is an additional argument in favour 

 of the view advanced by Mr. Garstang f, that such sheaths 

 contain a " plcuropodial element." 



Hancochia eiidactylota^ Gosse. (PL XVII. tig. 3.) 



A specimen of this species was dredged last summer (1891) 

 on Delesseria in Plymouth Sound, as I have alread}^ recorded J. 

 Mr. Hunt, the original discoverer of this form, dredged the 

 only ]M-evious British specimen on the same Alga in Tor Bay 

 in 1877. This was described by Mr. Gosse § under the name 

 Hancochia eudoctylota. In 1886 Prof. Trinciiese, apparently 

 in ignorance of Gosse's paper, described (" Ricerclie Anato- 

 miche sul Genere 6'oy«a "||, 1886) four specimens dredged 

 near Naples, defining them as two species of a new genus, 

 Govia rubra and 6r. viridis. Although the internal anatomy 

 of Hancochia is unknown, it seems probable that the genera 

 Govia and Hancochia will be united, as indeed has been done 

 by Dr. Norman in his " Revision " (this Journal, vol. vi. 

 1890, pp. 79, 80) . Cams (' Prodromus Faunae MediterrancEe,' 

 vol. ii. pt. 1, p. 208) writes the genus Govia^ Trinch., adding 

 in brackets [Hancochia, Gosse). 



The Plymouth specimen was about a quarter of an inch in 



♦ Norman, Aon. & Mag. Xat. Hist. 1877, xx. p. 518. 



t " Complete List of Opistliobrauchs at Plymoutli," .Toiirn. Mar. Biol. 

 Assoc, (n. s.) i. uo. 4, p. 430. 



X " The Occurrence of Hancochia at Plymouth," ihid. (n. s.) vol. ii 

 no. 2, p. 193. 



§ Ann. & Mag. Nat. Hist. ser. 4, vol. xx. 1877, p. 316. 



II Mem. dellaii. Ace. deUe Sc. dell' Instituto di Bologna, ser. o, vol. vii. 



