aplysiidjE. 865 



DoLABELLA, Laiiiarck. 



Etym. — Dolabella, a small hatchet. 



Distr. — 12 sp. Mediterranean, Mauritius, Ceylon, Society 

 Islands, Sandwich Islands. D. Teremidi (Ixxxix, 74, 75). 



Shell hard, calcareous, trigonal, with a curved and callous 

 apex. 



Animal like Aplysia, with gill near posterior extremity of the 

 body and lateral crests closely appressed, leaving only a nan-ow 

 opening ; ornamented with branching filaments. 



SiPHONOPYGE, Brown. 



Distr. — 6 sp. West America, Chinese Sea. S. lurida^ d'Orb. 

 (Ixsxix, 76, 77). 



Shell truncated in front ; foot-lobes spread oat for swimming; 

 posterior part extended beyond the siphon. 



NoTARCHUS, Cuvier. 



Etym. — Notos, the back, archos, vent. 



Sy7i. — Busiris (giHseus)^ Risso. 



Distr . — 7 sp. Mediterranean, Red Sea, living in floating 

 masses of sea-weed. N. ocellatus, Rang (Ixxxix. 78j. 



Animal ornamented with filaments, sometimes dendritic, foot 

 narrow, lateral crests united, leaving only a narrow branchial 

 slit ; gills not covered by an opercular mantle-lobe. 



Notarchus was long supposed to be without a shell ; it is 

 present, however, paucispiral, only a millimetre in diameter, and 

 concealed under the mantle at the posterior part of the visceral 

 mass. 



AcLESiA, Rang. 



Distr. — Several sp. East Indies. A. rufa, Quoy (Ixxxix, 79). 



Animal elongated, with a pointed posterior termination covered 

 with filiform appendages ; four long tentacles ; gills in a branchial 

 cavity. No shell. 



BuRSATELLA, Blaiuville. 



Distr. — B. Leachii, (Ixxxix, 80). 



Subglobular, the natatory appendages united together on the 

 back, leaving a dorsal cavity containing the anus and a large 

 free gill ; four ramified tentacles, and two buccal appendages. 

 No shell. Is possibly identical with Aclesia, the globular shape 

 being due, perhaps, to immersion in alcohol. 



Stylocheilus, Gould, 1841. 



Distr.- — 3 sp. New Guinea, on Fuci. S. longicauda, Quoy 

 (Ixxxix, 81 ). 



Animal limaciform ; cirrigerous, dilated at the sides, atten- 

 uated behind; neck distinct ; tentacles four, long, linear, papillose, 

 far apart ; lips dilated laterally into tentacular processes. 



