166 Trans. Acad. Sci. of St. Louis. 



ful result could be attained by pursuing such a course. 

 Monterosato has attempted it in a partial manner in the case 

 of the Mediterranean Daphnellids, but his genera, which in 

 my opinion will be proved ultimately valid, have been sup- 

 pressed by Cossmann and others. 



The name Daphnelliui is here adopted for the tribal des- 

 ignation, though the name Daphnella is antedated by both 

 Cythara and Mangelia, because both of the latter have been 

 called in question. Cossmann rejects Cythara altogether in 

 favor of Eucithara Fisch., and Mangelia is generally spelled 

 '' Mangilia'' by recent authors. These courses are both 

 erroneous, however, since there is no necessity for the sub- 

 stitution of Eacithara for the former, and the original spell- 

 ing of the latter is Mangelia, which being the case, it is 

 impossible to change it, in spite of the fact that the one 

 intended to be honored in the name loses this honor by reason 

 of the mistake. 



The two genera described below are both widely isolated in 

 the structure of the embryo and in other characters : — 



Eoclathurella u. gen. 



The shell in this genus is small in size, more or less elon- 

 gate, having when mature about three convex body whorls, 

 the aperture oblique and rather narrow, oval or sublinear, 

 much less than half as long as the shell, the sinus relatively 

 large, deep, semicircularly rounded, strongly everted and well 

 separated from the suture, the posterior callous promineace 

 well developed. The inner lip is callous throughout, bearing 

 three or four short transverse plicae at maturity, the canal 

 very short and generally not strongly differentiated. The 

 ribs are numerous, elongated and extend in gradually reduced 

 form to the suture above, the spiral lyrae rather small and 

 widely separated, but abruptly formed and slightly enlarged 

 on the ribs, the fasciolar surface convex, crossed by the rib- 

 bing but having finer and more close-set spirals. The embryo 

 it relatively large, broadly conical, closely coiled and of 

 between three and four whorls, the lowermost gradually 

 acquiring some longitudinal riblets which merge gradually 



