GENUS — SCALPELLUM. 215 



Genus — Scalpellum. Pis. V, VI. 



Scalpelltjm. Leach. Journ. de Physique, t. lxxxv, July, 1817. 



Lepas. Linn. Systeina Naturae, 1767. 



Pollicipes. Lamarck. Animaux saus Vertebres, 1818. 



Polylepas. Be Blainville. Diet, des Sc. Nat., 1824. 



Smilium (pars geueris). Leach. Zoolog. Journal, vol. 2, July, 



1825. 

 Calantica (pars geueris). /. E. Gray. Anuals of Philosophy, 



vol. x, (new series,) Aug. 1825. 

 Thaliella (pars geueris). /. E. Gray. Proc. Zoolog. Soc, 1848. 

 Anatifa. Quoy et Gaimard. Voyage de l'Astrolabe, 1826 — 34. 

 Xipiiidium (pars geueris). Dixon. Geology of Suffolk, 1850. 



{Herm. et Fcem.) Valvis 12 ad 15 : lateribus verticilli 

 inferioris quatuor vel sex, lineis incrementi pier unique 

 convergent 5 us : sub-rostrum rarissime adest : pedunculo 

 squamifero, rarissime nudo. 



(Herm. and Fern.) Valves 12 to 15 in number : latera 

 of the lower whorl, four or six, with their lines of growth 

 generally directed towards each other : sub-rostrum very 

 rarely present : peduncle squamiferous, most rarely naked 



Filamentary appendages, none : labrum, with the upper 

 part highly bullate : tropin, various : olfactory orifices, 

 more or less prominent : caudal appendages, uniarticulate 

 and spinose, or none. 



Males, parasitic at or near the orifice of the sack of the 

 female or of the hermaphrodite : thorax enclosed within 

 a capitulum, furnished with three or four rudimentary 

 valves, or with six perfect valves : peduncle either short 

 and distinct, or confounded with the capitulum : some- 

 times mouth and stomach absent, and cirri non-prehen- 

 sile ; sometimes mouth and cirri normal. 



Generally attached to horny corallines, in the warmer temperate seas over 

 the whole world. 



I have felt much doubt in limiting this genus : the six 

 recent species which it contains, differ more from each 

 other than do the species in the previous genera. Mr. 



