EMARGINULA. 249 



Subgenus Emarginula s. str. 

 Fissure an open slit in the front margin. 



Subgenus Rimula Defr. 

 Fissure a closed hole on the front slope. 



(Subgenus Emarginula s. s. 



As sections under Emarginula (restricted), I have placed two 

 groups : 



1. Nesta H. Ad., an elongated Emarginula with the recurved 

 apex posterior and marginal, and 



2. Emarginella Pils., proposed for a species of doubtful relation- 

 ships, the soft parts of which are so voluminous as to be far larger 

 than the shell. 



Species of the Mediterranean, the Atlantic, and the Gulf of Mexico. 

 E. huzardi Payraudeau. PI. 28, fig. 16. 



Shell depressed, oblong-ovate, posterior slope straight, half the 

 length of the convex front slope. Slit narrow, one-fifth to one-sixth 

 the length of the shell. Surface latticed by alternately larger and 

 smaller radiating riblets and delicate raised concentric lamina?, form- 

 ing compressed scales on the ribs and cutting the interstices into 

 pits. 



There are 25-28 primary radiating riblets ; the minute apex is 

 distinctly recurved ; the side margins are arched so that the shell 

 rests upon the ends only. Inside bluish-white ; a narrow callus ex- 

 tends from apex to slit, but there is no groove ; margin finely 

 denticulated. Length 11, breadth !■>, alt. 2* mill.; length 13, 

 breadth 8, alt. 4 mill. 



Mediterranean and Adriatic Seas. 



E. Imzardii Payr. Moll, de Corse, p. 92. t. 5, f. 1, 2, 1826.— Desh. 

 Exped. Sci. Moree iii, p. 134. — Piiilippi, Enum. Moll. Sicil. i, p. 

 115. — Weinkauff, Conch, des Mittelm. ii, p. 398. — Sows, in 

 Conch. Icon., t. 1, f. 4. — Buq. Dautz. & Dollf. Moll. Rouss., p. 

 449, t. 54, f 7, 8. — ? Patella scissa von Salis Reise ins Koen. Neap., 

 p. 359, t. 6, f. 1. — E. cusmichiana Brus., Contr. pella Fauna Dalm., 

 pp. 38, 81. — E. fissurelloides Nardo mss., teste Monterosato. — E. 

 depressa Risso, Eur. Merid., t. 10, f. 151, not E. depressa Blainville. 



More depressed than its allies, and having the apex nearer the 

 middle. 



