332 MANUAL OF THE MOLLUSCA. 



Crimora, a. and H. 



Body limaciform. Cloak nearly obsolete, forming a veil with 

 branched appendages over the head, and a papillated ridge on 

 the sides of the back. Dorsal tentacles laminated, retractile 

 within sheaths ; oral tentacles tubercular. Branchiae plumose, 

 non-retractile. Lingual teeth 26.0.26. 



Pelagella, Grube. 



Animal oblong ; tentacles sheathless ; head -veil witho;it pro- 

 cesses ; ridge along the middle of the back, and two lateral ones; 

 8 feathery gills arranged in a circle. 



Distribution, 1 species. South Europe. 



Gymnodoeis, Steenstrup. 



Animal oblong ; tentacles sheathless ; gills, with lateral pro- 

 cesses, dendritic, 2 or more in number. 

 Distribution, 1 species. Japan. 



AcAJSTTHODORis, Grube. 



Animal oblong ; tentacles sheathless ; retractile within a 

 cavity in the mantle ; several fleshy processes on the back ; 8 

 feathery non-retractile gills. 



Distribution, 2 species. North Sea. 



Casella, H. and A. Adams. 



Tentacles retractile within sheaths ; gills laminated, with 6 

 lobes. 



Distributio7i, 1 species. East India. 



Brachychlamis, Ehrenberg. 



Mantle long, angular ; tentacles in front of the edge of mantle. 

 Distribution, 1 species. East Africa. 



Fajiily YII. — Tritoniad^. 



Animal with laminated, plumose, or papillose gills, arranged 

 along the sides of the back ; tentacles retractile into sheaths ; 

 lingual membrane with 1 central and numerous lateral teeth ; 

 orifices on the right side. 



Tritonia, Cuvier. 

 Example, T. plebeia, PI. XIII., Fig. 7. 



Animal elongated ; tentacles with branched filaments ; veil 

 tuberculated or digitated ; gills in single series on a ridge down 



