300 PEOCEEDINGS OF THE GEOLOGICAL SOCIETY. [Feb. 21, 



Secondary granules none or indistinct ; primary tubercles simple, 

 deeply sunk, and very numerous and close-set towards the margins, 

 becoming more dispersed towards the peristome. The ambulacra 

 are somewhat raised above the general upper surface of the test ; 

 the pairs of pores are connected by oblique grooves ; the inner pores 

 are round, the outer ones slit. The general form is nearly hemi- 

 spherical, the antero -posterior but slightly exceeding the transverse 

 diameter, and the test being only slightly wider behind. The height 

 is about equal to half the transverse diameter. 



This species is closely allied to E. hcemisphcericus, Lam., and it 

 differs from that species chiefly in having more numerous and closer 

 primary tubercles, in the more open and less petaloid ambulacra, 

 and in having a large transverse vent. E. hemi splicer icus is found in 

 the miocene of Malta, and other localities. E. semiorbis occurs at 

 Anguilla, and it is used as a pound weight by the inhabitants. 



5. ECHINOLAMPAS LYCOPEESICUS, SpCC. UOV. PI. XIX. fig. 8. 



Test oval, wider behind than before ; upper surface convex, 

 margins tumid ; ambulacral summit subcentral ; ambulacra raised, 

 petaloid, extending nearly to the margins, base concave towards the 

 subpentagonal mouth ; tubercles small, numerous, and very closely 

 set, becoming large and somewhat more scattered towards the mouth, 

 which is subexcentrical and slightly notched by the termination of 

 the rows of pores continued from the ends of the ambulacral petals ; 

 anus large, transverse, oval, closely submarginal. 



The nearest species to this is E. seutiformis, Leske, found in Malta 

 and elsewhere. The present species is constantly smaller, and the 

 ambulacra appear to be longer and the summit more median. The 

 dorsum is more equally inflated, and there is no tendency to a sub- 

 conical form. 



Anguilla. 



6. ECHINOLAMPAS OVTTM-SEEPEN-TIS, SpCC. UOV. PL XIX. figS. 4-6. 



Test oval, subcylindrical or nearly circular, wider behind than 

 before, slightly rostrated anteriorly and truncate posteriorly, some- 

 times having a tendency to become polygonal; ambulacra raised, 

 petaloid, open at the ends, extending nearly to the tumid margins, 

 the pores connected by an oblique groove ; base convex, except 

 towards the mouth, where it becomes somewhat concave ; dorsum 

 rather evenly convex ; ambulacral summit subcentral ; anus small, 

 circular, situate between the peristome and the margin, much nearer 

 to the latter than to the former. 



This seems to be an extremely variable species, both as to general 

 shape and as to the form of the mouth. It is distinguished from the 

 preceding by its small circular vent and wider ambulacra. The 

 mouth is usually subpentagonal, but occasionally becomes transversely 

 oval. Some examples which approach the circular form have a 

 tendency to become subconical. 



San Fernando, Trinidad. 



