!:!. UI;i;.\M-MI ATA. 

 rdln modi 



iilfl- ' form a well marked escutcheon. In front (if ami beneath the I 



a deep lunule. Surface marked with regular, concentric fold-. oh-oletr on tin 

 ilinal -lope-, ami l-y tw.. ur three times more mimeiou- fine .stri.e, which seem to, 

 ha ded over all part-, of the -urf.i. 



This neat shell wa- at tir>t de-cril>ed as a Cnnxnni/'i. hut with the disco\ery of 

 the closely all; //.. it hecame evident at once that the specie- had been 



mi-placed. Compared with the type -pecies it is found to ditl'er in its form, the 

 <lor-al and ventral margin- being much le.ss cnr\ed and the outline decidedly nMoiitf 

 instead of rather hroadly oval. The iimlional ridj^e .1 unewhat lietter delined 



ami the anterior end of the shell project.- 1'eynml the beaks which is not the case in 

 lltf. 



CIMK M'M'K-TA 



PI s. -n. 



CM i -f modfitv* DI.KH ir. !-'J AIII.T. <; 100. 



Shell -mall, moderately ventricose, oliliijiiely ovate in outline, known from casts 

 of the interior only. In the>e the anterior end is very -mall, -harply rounded, 

 aKruptly d.'|,re ed beneath the l>eak-. projecting very little beyond them, and almost 

 entirely occupied liy a >uhcircular inu.-culiir scar, 1 teaks small, only -lightly incurved, 

 appearing I'rominent. I'mLonal ridge scarcely di-tiii^rui-halile. the cardinal slope 

 faintly concave between it and another low ridge-like swelling that forms the hack 

 of the ca-t. Along the hinge line there is a narrow impressed area. The lunule, 

 like the escutcheon, is proportionally narrower than in the other species. Shell 

 thin: hinge plate narrow, apparently with the characters (as shown by recently 

 obtained material) required l>y the genii-. 



A- near ieteimined from casts of the interior only, this -pecies would 



appear to occupy an intermediate po-itioi: 

 !>eing longer t han the tir-t and shorter than ti id. 



l 

 unth-x, M 



