A NEW ECHINOCORYS FROM BOLIVIA 



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if my interpretation is correct, in having a posterior pair of plates 

 occluded, as indicated. Centrally the plastron becomes increasingly 

 convex toward the periproct in which region it projects about 3 mm. 

 below the oral plane of the test. The abulacral plates number 



Figs. 1-3. — Echlnocorys (Ananychites) poznanskii sp. nov. i, lateral view; la, 

 sketch of arrangement of apical system; ib, sketch of plastron, comprising sixteen 

 plates; 2, dorsal view; 3, ventral view. 



eighteen or nineteen normal pairs from the apex to the ambitus, 

 very small at first and increasing regularly and rapidly in size down- 

 ward. The pores are very much obscured by incrustation, the 

 pore pairs being clearly seen only toward the equatorial region, 

 where they are large and central in position, that is, some distance 



