CHTHALAMUS. 109 



NELLTJS, Eetphochiton, Metopoma. Our Plate xii.-fig. 227, 

 228. PL xxiv. fig. 506, 507, 



CHITONELLUS. Lam. (From Chiton.) Separated by Lamarck 

 from Chiton, on account of the valves being placed at a 

 greater distance from each other, the soft integument of 

 the animal intervening. C. striatus. Philippines. PI. xxii. 

 fig. 228. 



CHLOEOSTOMA. Swainson. A sub-genus of "Trochin^." 

 Sw. (Trochus) of which C. argyrostoma is given as an example. 

 Sw. Lard. Cyclop, p. 350. 



CHORUS. Gray, 1850. Monoceros Griganteus. Lesson. 



CHRYSOAE. Montf. Probably a species of Oethoceeas. 



CHEYSODOMUS. Swainson, 1840. "Distinguished from Fusus, 

 by the comparative shortness of the basal channel, and the ven- 

 tricose or enlarged shape of the body whorl. The beautiful 

 orange-mouthed Whelk of England is a typical example ; and 

 the few others now known are of a very large size, and chiefly 

 found in Korthern Seas, where they represent the more elegant 

 Eusi of tropical latitudes; the outer lip is always thin and 

 smooth." Sw. p. 90, paragraph 78, described at page 308. 



CHEYSOLUS. Montf. Poltstomella, B1. A genus of micro- 

 scopic Eoraminifera. 



CHEYSOSTOMA. Swainson, 1840. A genus of the family 

 " Eotellitise," Sw. Thus described, " Shell turbinate ; the whorls 

 few and convex ; aperture effuse, round ; inner lip thickened 

 just over, and almost concealing the umbilicus. Nicobaricus, 

 Martini, 182 fig. 1822—5." Sw. Lard. Cyclop. Malac. p. 327. 

 PL XXV. fig. 542. 



CHTHALAMUS. Eanz. Fam. Balanidea, BL Order, Sessile 

 Cirripedes, Lam. — Descr. " Shell much depressed, valves thick, 

 thickened at the base, with prominent areas ; operculum nearly 

 horizontal, composed of four valves." — Obs. This description 

 would apply generically to the shell called Platylepas in the 

 British Museum, only nothing is said about the prominent 

 plates jutting from the internal surface of the valves. The 



