oi~\ q 



'lype locality- .- ^':' -^en, Jamaica. 



Reroarlrs .- V. acaris is represented by a rather larrre num- 

 ber of inrt-ivi duals. i?he sculptiire ooiosists of eighteen to t\^enty 

 ■."•ell-def iner' ribs, ornamented vath lov; nodules, the r - ■'' '^^ <- s sepa- 

 rated by narrow impressed lines. In addition to these ribs there 

 is adjacent to the mars'in of the Innule a short row of re.^-nlar, ob- 

 lique rugae that represent the nodules of the adjoining ribs. At 

 the margin of the escutoheon a similar but shorter series is u.su- 

 ally developed snd first fe^-' r)osterior ribs ere weak with the 

 nodules somewhat roux-ded. ■'■'he lunule Is sharrjlj' set off from the 

 sculptured portion, but the escutcheon, which is longer and narrow- 

 er than the luiuile, is usuallj? less distinctly defiried; both are 

 elevated toward the hinge in consequence of the decir'' '' Ickening 

 of ■" ;;.rtn.ns, especially on the right valve. The hinge is strong, 



the ri?-ht valve v:ith an elonrated anterior and shorter posterior 

 cardinal and a posterior lateral; the left v,'ith a broad, obt^ase, 

 median cardinal and anterior lateral. 'Ihe height of the shell usu- 

 a"^, ly e-TC eds the width. -i^his small, aberrsnt form is ou.ite riistinct, 



Occurrence .- T,ower Pliocene : Bowden beds, "Bov-'den, Jamaica. 



