- 104 



Remarks .- A. endonena is represented hi one valve. Some of 

 the characters sagg-est that its oroper nlace is in the section 

 Acar, but the cardinal area is too wide. It differs from the young 

 of A. c and i cJ a o f the same size by being more elons'atecl, but less 

 produced at the postero-ventral an,?-le , more inflated, with higher 

 urabones and less conspicuously developed concentric sculpture. 



Ocourrence .- laver Iliocene: Bowd©n,beds, Bo-"den, Jamaica. 



