122 Mr. A. Adams on Gasteropodous Mollusca 
broken off. It has the aspect of a Pyramidellid ; but, from 
the absence of plaits on the columella, I should pr efer to place 
it with the Rissoids. 
Genus Corena, A. Ad. 
Testa tat aden rimata, spira apice obtusa; apertura cireu- 
ari, peritr uo; labio cal ui expanso obte cto, et 
aene abai acia instructo ; labro margine duplicato, extus 
valde r 
Honest in form some species of the little Bulimoid group 
called Ena by Leach; but it has a double peritreme, and the 
inner lip is furnished posteriorly with a dentiform tubercle. 
enus seems nearer Onoba than any other form with 
which I am acquainted. 
C. tuberculifera, A. Ad. 
C. testa elato-turrita, rimata, albida, tenui, subpellucida, apice spira 
obtusa; anfr. 5, convexiusculis, longitudinaliter oblique striatis. 
Hab. Gulf of Suez. 
Genus Rissoa, Fréminv. 
R. gracilis, A. Ad. 
R. testa aciculato-turrita, alba, solida, in medio convexiuscula ; 
anfr. 8, convexis, longitudinaliter catita. costis confertis ; aper- 
tura ovata ; labro arcuato, dilatato 
Hab. Gulf of Suez. . 
The only species of Rissoa proper which at all resembles 
this very elegant little shell is 2. awriscalpium, Linn., whic 
however, is much larger, and has not the regular, longitudinal, 
rather crowded ribs of this shell. Only a single specimen was 
obtained. 
Genus Onosa, H. & A. Ad. 
O. mirifica, A. Ad. Ann. &. Mag. Nat. Hist. 1863. 
Hab. Gulf of Suez (M'Andr.), Japan (A. Ad.). 
Genus FENELLA, A. Ad. 
1. F. pupoides, A. Ad. Ann. & Mag. Nat. Hist. 1860. 
Hab. Gulf of Suez (M'Andr.), Japan (A. Ad.). 
2. P. n A. Ad. (Dunkeria), Ann. & Mag. Nat. Hist. 
Hab. Gulf of Suez (M'Andr.), Japan (A. Ad.). 
