378 POLYCERID^. 



Plocamophorus, Riippell and Leuckart, 1828. 



Syn. — Plocamoceros, Cuv., 1830. Plocamophorus, Gray, 1842. 

 Peplidia, Lowe, 1842. Histiophorus, Pease, 1860. 



Distr. — 10 sp. Red Sea, Australasia. P. ocellatus (xc, 5). 



Body limaciforai. Mantle represented by a supracapital veil 

 bearing tubereulate or branched appendages on the margin, and 

 by two or threfe tubercular processes upon each side of the back. 

 Rhinophores laminate. Oral tentacles flat. Branchiae few, non- 

 retractile. Tail dorsally carinated. Odontophore with the 

 spines near the middle bicuspid, none median in position. An 

 incomplete buccal collar. 



Ji]Gmus, Loven, 1846. 



Distr. — 3 sp. European coasts. JE. puiictilucens, d'Orb. 

 (xc, 6, 7). 



Body convex, covered with large tubercles. Mantle indis- 

 tinct, represented by a supracapital veil, and by a tubercular 

 ridge along each side. Rhinophores linear, smooth or hispid. 

 Branchiae non-retractile. Odontophore with simple, curved, 

 lateral spines ; no central spine. An upper corneous jaw. 



NoTODORis, Bergh, 1875. 



Distr. — N. citrina, Bergh. Rarotonga. 



Body limaciform (the back not distinct from the sides). 

 Rhinophores smooth, retractile in cavities protected by valves. 

 No buccal armature. Lingual teeth, none median, the lateral 

 ones erect and hook-shaped. — Bergh. 



Ceratosoma, Ad. and Reeve, 1848. 



Distr. — 8 sp. Australasia and Canary Isles. C. coi'nigerum, 

 Ads. and Reeve (xc, 8). 



Bodj^ elongate, prismatic, smooth, ending in a bluntly pointed 

 tail ; the dorsal surface passes into a post-branchial flesh protu- 

 berance. Mantle obsolete. Rhinophores laminated. Branchiae 

 with the roots more or less coherent, placed in front of and par- 

 tially around the tubular anus, with which they are retractile 

 into a common, smoothly margined cavity. Odontophore with 

 numerous rows of simple spines, none of which are central. A 

 spinous buccal collar. 



Trevelyana, Kelaart, 1858. 



Syn. — Gymnodoris, Stimpson, 1855. Stenodoris, Pease, 1866. 



Distr. — 11 sp. Red Sea, Indian Ocean and Australasia. T. 

 Geylonica, Kelaart (xc, 9). 



Body limaciform, rather swollen or raised on the central region. 

 Mantle obsolete ; no appendages ; rhinophores laminated and 



