CLIONEID^. 35 



Order II. GYMNOSOMATA. 



Body naked, without any shell. 



Head distinct. 



Wings 2 or 4, at the junction between the head and the body, with- 



a central intermediate lobe or rudimentary foot. 

 Gills exterior. 



Pteropodia oligoptera, part, Rafin. Anal. Nat. 1815. 



Clionidia, Rafin. Anal. Nat. 1815. 



Gymnosomata, Blainv., Rang, Mann. Moll. 117. 



Gymnosoma, Blainv. Malac. 482, 1825. 



Pterobranchia, § e. Gray, Med. Repos. 1821, 235. 



Procephalis, Latreille, Fam. Nat. 1825. 



Pneumodermi, UOrh. Moll. Cuba, i. 70, 1841. 



Les Clios, Rang, Man. Moll. 117. 



Cliodinae, Menke, Syn. 5, 1828. 



Clioidae, Menke, Syn. ed. 2, 9, 1830 ; Wiegm. Hand. Zool. 517, 



1842. 

 Clionina, Bronn, Gesch. d. Naturg. iii. 353. 

 Acephales, part, Blainv. Bull. Soc. Phil. 1814, 179. 



Fam. V. CLIONEID^. 



Animal fusiform. Head with a series of conical prominences on 

 each side. Wings 2, with a central foot-like appendage. 



Clionidea, part, Rafin. Anal. Nat. 1815. 



Clionea, Oken, Lehrb. 1815. 



Cliones (Les Clios), Ferussac, Tabl. Sys. 25, 1821 ; Rang, Man. 

 Moll. 117, 1829. 



ClionidaB, Gray, Syn. Brit. Mus. 1840 ; Proc. Zool. Soc. 1847. 



Cliodinee, part, Menke, Syn. 5, 1828. 



Clioidae, part, Menke, Syn. ed. 2, 9, 1830 ; Wiegm. Handb. Zool. 

 517, ed. 2, 545. 



MoUusca nuda nageant, part, Latr. Diet. Hist. Nat. xxiv. 109, 1804. 



Synopsis of the Genera. 



1. Clione. Head indistinct. Tentacula distinct. 



2. Cliodita. Head distinct. Tentacula not apparent. 



