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is conspicuously longer than the posterior one, is slightly convex, but nearly straight towards 

 the apex, posterior slope a little concave near the apex and towards the margin, convex in 

 the middle part, side-slopes straight, only a little concave near the margin, with a very small 

 concavity near the apex. Nucleus compressed, subspiral, smooth under a lens, but with very 

 small pits under the microscope; it is placed at about r '/ n of the total length. 



Sculpture consisting of rather strong, elevated, concentric striae, less strong but more 

 numerous than in the preceding species, crossed by weaker, but still very conspicuous radiating 

 striae, o-iving to the shell a somewhat cancellated appearance. Inside of the shell smooth. 



Long. 5 1 /,, lat. 4 s / 4 , alt. 2 iMill. 



The foot of the animal with 2 epipodial filaments. 



This species is closely allied to C. alveolata Schepm. but differs by its much more elevated 

 apex and weaker sculpture; from C. Icptalea Verrill and C. cingulata Schepm. it differs by its 

 weaker concentric striae, and the nucleus is placed much more near the centre. 



The radula lias a rhachidian tooth (R) of an oblong shape, broader near the front than 

 at the posterior margin, with curved sides, the front margin is convex and like the side margins 

 thickened, this thickening forms in the centre a point directed towards the base; this tooth has 

 a small simple cusp. The elongated first (1) and second (2) laterals, have tricuspid cusps, the 

 third (3) has only a simple cusp. The cusp of the fourth lateral (4) is large, divided into two 

 denticles, the lower or distal one is the smallest. The uncini (U) have rather short, thick cusps, 

 with indistinct denticles. 



5. Cocculina alveolata n. sp. PI. I, fig. 8; PI. VIII, fig. 11. 



Stat. 312. Saleh-bay, North coast of Sumbawa. 274 M., fine, sandy mud. 3 Spec. 



Shell small, patelliform, oval, depressed, pellucid, white, with small patches of a thin, 

 yellowish epidermis ; ends broaclly rounded and elevated ; anterior, posterior and side-slopes 

 convex, with only a slight depression behind the depressed apex. Nucleus very much depressed, 

 compressed, scarcely spirally striated under a lens, but under the microscope the nucleus is 

 covered by rows of conspicuous alveoli (much more conspicuous than in the preceding species). 

 It is placed at about 5 / 9 ot " tlie length of the shell, the front slope being the largest. 



The sculpture consists of conspicuously elevated concentric striae, of which a few are 

 stronger than the rest, they are crossed by radial striae, which are but slightly weaker, a little 

 wavecl and make the concentric striae slightly beaded, especially the stronger ones. The shell 

 is still more cancellated than in the preceding species. Inside shining. 



Long. 4 1 /,, lat. 3 1 /,, alt. i 1 /, Mill. 



Foot of the animal with epipodial filaments. 



This species, as already mentioned, differs from the preceding one, by its depressed apex 

 and stronger sculpture, moreover by the convex slopes and the much larger pits or alveoli of the 

 nucleus, this character being not visible in C. ovata with the same lens as in the present species. 



I examined the radula of one of the specimens. This agreed in every respect with those 

 of the other species of Cocculina, examined by Thiele and by me, but the median tooth wanted; 



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