LEPAS HILLII. 77 



L. anserifera and L. Hittii are surprisingly alike, though in 

 L. anatifera alone, the uppermost part of the peduncle is 

 dark. As far as I have seen, the smoothness of the 

 valves, together with the presence of a tooth beneath the 

 umbo, on the right-hand scutum, and its entire absence 

 on the left side, (in other species it is smaller on this, 

 than on the right-hand side,) is an unfailing diagnostic 

 mark. I believe this species is always attached to float- 

 ing objects, though there are some very young specimens 

 in the British Museum, collected by Sir G. Grey, adher- 

 ing to sandstone, but this may have been buoyed up by 

 some large sea-weed. Mr. Peach has given me the 

 particulars of two instances, in which, after gales of wind, 

 this species, of nearly full size, adhering to apparently 

 freshly broken-ofTLaminarise, has been cast upon the coast 

 of England and Scotland. 



2. Lepas Hillii. (PL I, fig. 2). 



Anatifa vel pentalasmis l^evis (!) plerumque auctorum. 

 Pentalasmis Hillii (!). Leach. Tuckey's Congo Expedit. p. 413, 



1818. 



— CHELONL& (!) lb. lb. 



Anatifa tricolor (?). Qiwi/et Gaimard. Ann. des Sc. Nat., 1st 

 series, torn, x, 1827, PL vii, fig. 7, et Voyage de 

 1' Astrolabe, PL xciii, fig. 4. 

 — substriata (!). Conrad. Journal Acad. Nat. Sc, Phila- 

 delphia, vol. vii, 1837, p. 262, PL xx, fig. 14. 



L. valvis Icevibus ; scutorum dentibus internis umbo- 

 nalibus nullis ; carina a cater is valvis, J wrcd etiam a scu- 

 torum basali margine, paululum distante ; pedunculi parte 

 superior e aut pallida aid aurantiacd. 



Valves smooth; scuta destitute of internal umbonal 

 teeth; carina standing a little separate from the other 

 valves, with the fork not close to the basal margin of the 

 scuta ; uppermost part of peduncle either pale or orange- 

 coloured. 



Filaments three on each side. 



