10 PLEIOCENE FOSSILS. 



doubled round the fore-shell. In form it was probably a broad oval, still shorter and more 

 circular than the living species which it most resembles. 



I take pleasure in inscribing this species to Prof. Holmes, to whose efforts we owe the 

 discovery, not only of a large portion of these fragments, but of many other important 

 remains from the Tertiary of South-Carolina. 



Plate III., Fig. 2. Lower part of the hinder half -row from the right ambulacrum of the forward 

 pair, with forward half -row of the inter ambulacrum immediately behind. 

 " 2a. JSr east-plate, nearly entire. 



Locality. Smith's, Goose Creek. (J. McC.) 



Museum, College of Charleston, 8. C. 



PLAGIONOTUS RAVENELIANUS.— McCrady. 

 Plate III., Fig. 3, 3a. 



Fragmenta quae Plagionotum stellae ambulacralis membris paribus anterioribus longis 

 arcuatisque, et posterioribus probabile est curtis ; duorum fragmentorum assulis fascioliferis 

 tuber culorum maximorum or dine deprivatis ; jugis descendentibus interambulacrorum parium 

 posteriorum valde remotis ; fasciola peripetali anteriorem testam duplicata ; stemo lato et 

 aliquantum triangulari indicant. Probabile est — quod anteriora latissima, posteriora curta, 

 angusta fuit, animalis forma. 



I have given the above name to a portion of the fragments found in the Pleiocene, which 

 differ from those attributed to P. Holmesii, in having the intervals between the plate ridges 

 of the second pair of inter-ambulacra greater, the forward pair of ambulacra relatively 

 longer and more bent backwards, and the hinder pair probably shorter ; the sternal plate, 

 fig. 3a, somewhat broader, shorter, more massive, and inclined to the triangular form. It 

 is probable, also, that this species was broader across the fore-shell and narrower behind 

 than P. Holmesii, with perhaps a less relative distance between the anal facet and the 

 sexual centre. Perhaps, also, the belt-bearing-plates were entirely deprived of the ordinary 

 rows of large knops, for the whole circuit of the star-belt. 



I have gladly availed myself of this opportunity to connect with one of the forms of this 



