GASTEROPODA. 329 
Sub-genus. Oncidoris (Bl?). D. bilamellata, Johnst. Back 
elevated, tuberculose; gills non-retractile; oral tentacles fused 
into a veil; buccal mass with a gizzard-like appendage; lingual 
teeth 2in each row. (A. and H.) 
D. scutigera (Villiersia), D’Orbigny, Rochelle ; has the mantle 
more than usually strengthened with calcareous spicula. 
Distribution, 100 species. 
The Dorids vary in length from 3 lines to more than 8 inches, 
they feed on zoophytes and sponges, and are most plentiful on 
rocky coasts, near low water, but range as low as 25 fathoms. 
They occur in all seas, from Norway to the Pacific. 
HEPTABRANCHUS, A. Adams. 
_ Mantle without a longitudinal ridge on the back; 7 gills 
arranged in a semicircle; oral tentacles star-shaped. 
HEXABRANCHUS, Ehrenberg. 
Same as last, but with 6 gills arranged in a cross on the hinder 
part of the body; oral tentacles notched. 
ATAGEMA, Grube. 
Mantle with longitudinal ridge on the back; tentacles clavate, 
retractile; gills very small. 
Distribution, 1 species. New Zealand. 
Actinocycius, Ehrenberg. 
Animal ovate; back naked; gills very plumose. 
Distribution, 7 species. Hast Africa and South Europe. 
CHROMODORIS. 
Animal almost quadrangular; back naked; feathery gills 
arranged lineally. 
Distribution, 1 species. East India. 
ASTERONOTUS, Ehrenberg. 
om ovate: the apertures for the gills and tentacles almost 
closed. 
Distribution, 2 species. Hast Africa and South Europe. 
GLossoporIs, Ehrenberg. 
Synonym, Pterodoris, Eb. 
Tentacles retractile; back covered with unequal cylindrical 
processes ; a thread-like process on each side of the fore part of 
the foot. 
Distribution, 7 species. East India and West America. 
