672 SYSTEMATIC PALEONTOLOGY 



fcrent individual internal casts of the species under four different spe- 

 cific heads. His figures 18 and 19 of C. eufalense represent a more 

 than usually gibbous cast of this species, the true C. eufalense being 

 a fundamentally different shell without the spines rising from the inter- 

 spaces between the ribs, and consequently not even a member of the sub- 

 genus Criocardium. Whitfield' s figures 10 and 11 of C. dumosum repre- 

 sent a more than usually rounded form of the species under discussion, 

 the specimen is larger, more convex and has a steeper posterior slope than 

 the true C. dumosum. Figure 12 of the same author, an enlargement to 

 illustrate the surface characters of C. dumosum, also proves, upon exami- 

 nation of the specimen, to be taken from a member of the species under 

 consideration; the illustration is not an accurate representation of the 

 characters of the specimen, the costse being too narrow, the interspaces 

 too wide, and the spines not enough compressed laterally. The internal 

 cast used by Whitfield as the original for his figures 1 and 2 of C. multi- 

 radiatum seems to be a member of this species also; a specimen in the 

 recent collections of the Survey from the Navesink marl near Crawfords 

 Corner agrees almost exactly with this illustration, and it is undoubtedly 

 a member of the species under discussion. The enlarged illustration, 

 figure 3, given to represent the surface characters of this same species, is 

 much overdrawn, the original mould from which the gutta-percha impres- 

 sion was taken being altogether too imperfect to show to what species it 

 belongs." Weller, 1907. 



The casts of C. tenuistriatum Whitfield are readily separable from those 

 of C. dumosum Conrad by the much higher relative altitude and the trun- 

 cated posterior margin. The resemblance to the casts of C. kiimmeU 

 Weller is much closer, but the umbones are somewhat less elevated and 

 less acute and the anterior adductor muscle scar much less prominent. 



Occurrence. MATAWAN FORMATION. Park Point, and ? Ulmstead 

 Point, Anne Arundel County. MONMOUTH FORMATION. ? Jones farm, 

 Burklow's Creek, Cecil County. 



Collections. Maryland Geological Survey, Columbia Univerisity, Xew 

 Jersey Geological Survey. 



