MALACOZOA. GASTEROPODA. NUDIBI^ANCHIATA, 69 



1. Hcilia Flemingidna. — Shell obovate, thin, glossy, 

 "white, with faint striae. Named after Dr. Fleming. 



Genus 4. Bullina. — Shell cylindrical, involute, the 

 last turn concealing the rest ; the spire generally sunk : 

 the aperture straight, very narrow, a little widened ante- 

 riorly. Named from Bulla. Ferussac. 



1. Bullina umbilicdta. — Shell oblongo- cylindrical, 

 semitransparent, glossy, with faint growth-lines, the 

 posterior extremity rounded, with a deep and narrow 

 umbilicus. Umbilicatus, having a pit in the spire. 



2. Bullina trunccita. — Shell sub cylindrical, thin, semi- 

 transparent, glossy, with distinct shallow sulci on half 

 its length from the posterior extremity, which is truncate, 

 with a wide and shallow umbilicus. TruncdtuSy cut off 

 at the end. 



3. Bullina cylindrdcea. — Shell cylindrical, thin, trans- 

 parent, glossy, smooth, or with faint growth-lines, sub- 

 truncate with a deep umbihcus. Cylindrdceus, elon- 

 gated and round. 



ORDER VIIT.— GASTEROPODA NUDIBRANCHIATA. 



Respiratory apparatus consisting of branchial tufts 

 or papillae, placed on the back, and exposed. 



Tritonia, Lamarck. Polyhranchiata and Cyclobranchi- 



atUy Blainville. Nudibranchiatay Cuner. Nudusy bare ; 



branchicBy gills. 



Polybranchiata. 

 With numerous IrancMce on the sides of the body. 



Family I. — ^olidina. 

 Body oval, oblong, or elongated, with papiUiform or 

 filamentous branchiae disposed along the sides of the 

 body above ; two pairs of tentacula ; eyes behind the 

 "upper. Named from the Genus ^Eolis. 



Genus 1. ^olis. — Body oblong, tapering to a point, 

 with numerous filamentous or papiUiform branchiae in 

 rows on the sides above. Name from uEolus. Cuvier. 



