Suborder NUDIBRANCHIATA. 



Naked hermaphroditic opisthobranchiate Mollusca, gener- 

 ally of symmetrical, slug-like form ; without a shell in the adult 

 state. Ctenidium and osphradium absent; symmetrical accessory 

 respiratory appendages usually developed from the dorsal integu- 

 ment, rarely from the sides. Central nervous system concentrated. 

 Radula usually strong, the teeth uni- or multiserial. Kidney not 

 compact. 



Tribe I. Doridoidea. 



Genital duct triaulic, liver completely inclosed in the visceral 

 mass, female duct bifurcated. Anal aperture postero-median 

 upon the dorsum, surrounded by the branchial rosette, or rarely 

 between the perinotaeum and the foot. 



Family DORIDIDAE. 



Branchial plumes in an arc or circle, usually joined together 

 at their bases, usually retractile into a common cavity. Rhino- 

 phores always with perfoliate clavus. Pharyngeal bulb never 

 suctorial. 



Subfamily DISCODORIDINAE. 



Body not hard, depressed ; the dorsum minutely granu- 

 ligerous. Mantle margin rather wide ; tentacles digitiform ; 

 branchial plumes usually tri- or quadripinnate ; foot rather wide. 



Labial armature made up of minute, closely set rods. Rha- 

 chis of radula naked, the pleurae multidentate, the teeth hooked. 



Penis usually unarmed. 



Three specimens of Dorididae were found in the collection, 

 all of them being apparently new species. 



