CATALOGUE OF PTEROPODA. 



Order I. THECOSOMATA. 



Body inclosed in a shell. 



Head indistinct, with two wings on the sides of the mouth. 

 Gills internal. Tooth of lingual membrane hooked, with a strong 

 hooked tooth on each side. — Loven, t. 3, f. 5, 6. 



Thecosoma, Blainv. Diet. Sci. Nat. xxxii. 271 (1824) ; Malac. 480 



(1825). 

 Thecosomata, ''Blainv." Rang. Man. 112; Gray, Syn. B. M. 1842, 



86, 92 ; Proc. Zool. Soc. 1848, 203. 

 Cryptocephala, Latr. Fam. Nat. 169, 1825. 

 Pterobranchia and Dactyliobranchia, Gray, Loud. Med. Rep. 1821, 



235. 

 Fam. Hvalea, Ferussac. 

 Hyales, ^Rang, Man. Moll. 112 (1829). 

 Hyalaeacea, Menke, Syn. 1830. 

 Hyalinees, DOrh. Voy. Amer. Merid. 77. 

 Hyalidees, Hyalidae, D'Orb. Moll. Cuba, 70, 71, 1841. 



Sub-order I. Body and shell straight or globular. Operculum none. 



Fam I. CAVOLINIDiE. 



Animal with two united fins, without any posterior foot-like ap- 

 pendage between them. Abdomen voluminous. Gills in pairs, 

 internal superior organs of generation on right side. 



Shell calcareous, symmetrical, elongate or globular. 



Dactyliobranchia, Gray, Land. Med. Bepos. 1821. 



Cleodoridae, Gray, Syn. Brit. Mus. 184 ; Proc. Zool. Soc. 1848, 



203 ; Fig. Mol. Anim. i. t. 77, 78. 

 Hyaleae (Les Hyales), Ferus. Tabl. 25, 1821; Rang, Man. 112, 



*1829 ; Desh. Ency. Meth. iii. 310. 

 Hyalaeacese (Hyaleaceae), Menke, Syn. 4, 1828. 

 Hyalaeacea, Menke, Syn. ed. 2, 6, 1830. 

 Hyaleacea, Herrmannsen, Gen. i. 543, 1846. 

 Hyalidse (or Hyaleidae), Cantraine, Malac. Medit. 22, 1841. 

 Acephalacis inequivalvibus bivalvibus, Lamk. Syst. 139. 

 HyalidEB, UOrb. Moll. Canar. 1837; Moll. Cuba, i. 70, 1841. 

 Acephales, part, Latr. Diet. Hist. Nat. xxiv. 119, 1804; Blainv. 



Bull. Soc. Phil. 1814, 179. 



