SCISSURELLA. 51 



while the usual growth striae are not lacking. In the example 

 figured in the Description of Egypt there is a deep groove between 

 the keel and the upper of the two spiral lirae ; in the examples 

 observed by me the groove is very shallow, and bears an elevated 

 line. The umbilicus is moderate, the aperture obliquely ovate. 



Diam. about H mill. {Phil.) 



Red Sea. 



Audouin's Descript. de l'Egypte, Coq., t. 5, f. 30 (no descript.). — 

 S. d'Orbignyi And., Phil., Conchyl. Cab., p. 38, t. 6, f. 10. 



S. reticulata Philippi. Vol. XI, pi. 67, figs. 49, 50, 51. 



The shell is thin, transparent, glassy, white, ovate, rather de- 

 pressed, but with convex whorls, and consists of 3? pretty rapidly 

 increasing whorls. The striae of growth are cut into a reticulation 

 by impressed transverse lines. The umbilicus is moderate, showing 

 none of the whorls ; the aperture is obliquely ovate. 



Diam. 2 mill. {Phil.) 



Bed Sea. 



S. decussata Audouin, Desc. l'Egypte, t. 5, f. 29 (not S. decussata 

 Orbigny, a fossil species). — S. reticulata Philippi, Conchyl. Cab., p. 

 38, t. 6,f. 11. 



S. koeneni O. Semper. PI. 57, figs. 17, 18. 



Shell small, fragile, subpellucid, rather narrowly umbilicated, 

 orbicularly depressed; first whorl embryonic; second sculptured, 

 angular, convex below the angle, the anal fasciole situated on the 

 angle very densely encircled with spiral lines, and with remote, in- 

 flexed longitudinal lamellae; anal fasciole a little immersed, its mar- 

 gins lamellose, elevated ; aperture rotund, the slit subangulate. 



Alt. 1, diam. If mill. {Semper.) 



Bohol, Philippines. 



S. koeneni Semper, Journ. de Conchyl. 1865, p. 286, t. 12, f. 3. 



S. hoernesi 0. Semper. PI. 57, figs. 15, 16. 



Shell very small, very fragile, greenish, narrowly umbilicated, 

 orbicular, depressed ; first whorl embryonic, smooth ; second whorl 

 sculptured ; whorls convex, with incurved lougitudinal lamella? and 

 very delicate encircling striae ; median slit-fasciole commencing on 

 the penultimate whorl, simulating a carina, finely striate longitu- 

 dinally, margins sublamellose ; aperture oblique, rotund. 



Alt. 1, diam. li mill. {Semper.) 



Luzon, Philippines. 



The slit-fasciole is not visible on the whorls of the spire. 



