BRITISH NUDIBRANCHIATE MOLLUSCA. 



xv 



Section 2. With the branchiae on the upper side of the cloak. 



Fam. 5. TritoniadjE. Body subquadrilateral ; cloak small; veil large ; ^ 



projecting in front of the head ; branchiae arranged on the > 19. Tritonia. 



pallial ridge ; anus lateral; jaws large . . J 



Fam. 6. Scyll^id,e. Body compressed ; cloak produced into lateral ^ 



lobes, bearing the branchial plumes; anus lateral; mouth with [-20. Scylhea. 



jaws . . . . ) 



Tribe 2. Liver diffused ; branchiae papillose, simple, or branched. 



Section 1. With a posterior central gastro-hepatic vessel; reproductive organs with a 



single external orifice. 



a. With the posterior vessel of the gastro-hepatic system below the ovary. 



Fam. 7. DendronotidjE. Tentacles 2, dorsal, usually laminated and "^ 21. Dendronotus. 



retractile within sheaths; branchiae branched or papillose, in a [22. Bornellia. 



single series along the sides of the back; veil small; anus 23. Lomanotus. 



lateral; mouth with jaws . . J 24. Hero. 



Fam. 8. Tethid^e. Body depressed; cloak indistinct; veil very large, "} 



funnel-shaped; tentacles 2, dorsal; branchial plumes alter- >-25. Tethys. 



nating with papillae ; anus latero-dorsal ; no jaws . ) 



Fam. 9. MELTBiDiE. Cloak wanting ; tentacles 2, simple, retractile within "^ 



sheaths; branchiae clavate, muricated or tuberculated, set in I 26. Melibe. 



single series on each side of the back ; anus latero-dorsal ; no | 27. Doto. 



jaws . . J 



Fam. 10. ProctonotidjE. Body depressed; tentacles 4, dorsal pair non- "") 



28. Proctonotus. 



retractile, without sheaths, oral pair small ; branchiae fusiform, 

 arranged on an obsolete pallial ridge, on each side of the J> . 



back, and in front of the head ; anus postero-dorsal ; mouth 

 with jaws . . . . . 



Fam. 11. Glaucid^;. Body elongated; tentacles 4, linear, simple, non- ~\ 



retractile ; branchiae arranged in a palmate form on extended V 30. Glaucus. 

 footstalks; anus lateral; mouth with jaws . J 



b. With the posterior vessel of the gastro-hepatic system above the ovary. 



f31. Calma. 



32. Flabellina. 



33. Facelina. 



34. Coryphella. 



35. Favorinus. 



36. Phidiana. 



37. Eolis. 



38. Cuthona. 



39. Cavolina. 



40. Galvina. 



41. Tergipes. 



42. Embletonia. 



Fam. 12. Eolidid^e. Without cloak ; tentacles 4, non-retractile, variable ; 

 branchiae simple, papillose or linear; anus lateral; mouth 

 with jaws . 



