92 FOSSIL ECHINI OF THE WEST INDIES. 



150 to each other]; the posterior I and V longer, very arcuate, forming 

 between them an acute angle [of about 55] posteriorly. Poriferous areas 

 are wide, depressed, with rounded, very open pores, united by a furrow 

 and strongly channeled. Tubercles are of two kinds; the larger are medium- 

 sized, unequal, scrobiculate, irregularly disposed, and circumscribed by 

 the peripetalous fascicle. These tubercles are less abundant and smaller 

 in the posterior interambulacrum. The smaller tubercles are crowded 

 and abundant, very fine above the ambitus, a little larger inframarginally 

 and on the elevation of the posterior interambulacrum ventrally. They 

 are more widely spaced toward the peristome and on the ventral surface 

 leave nearly smooth the areas of the posterior ambulacra. The peristome 

 is subcircular, a little elongated, excentric anteriorly. The periproct is oval, 

 opening at the summit of the posterior face. The peripetalous and the 

 anal fascicles are observable only at some points. They appear to be very 

 little sinuous. 



There are 2 specimens in the U. S. National Museum. The larger 

 measures 18 mm. in height, 47 mm. in length, and 33 mm. in width; the 

 smaller specimen measures 17 mm. in height, 38 mm. in length, and 31 

 mm. in width. The smaller specimen (my plate 16, figs. 5 and 6) is the 

 better preserved of the two and more closely agrees with Cotteau's 

 specific description. It is apparently the original of his plate 7, figures 

 8 to II. 1 This specimen is broadly rounded anteriorly, presenting one 

 nearly continuous curve from one side around the border to the other; 

 posteriorly it is much narrower and truncate. The larger specimen (my 

 plate 16, figs. 3 and 4), which is apparently the original of Cotteau's 

 plate 7, figure 12, is in shape almost the exact reverse of the small speci- 

 men. It is narrowly rounded and truncate anteriorly and broadly 

 rounded posteriorly, presenting one nearly continuous curve from one 

 side around the border to the other side. The test is widest distinctly 

 posterior to the middle. The anterior petals II and IV are markedly 

 wider than the same petals of the smaller specimen and the petals of the 

 posterior ambulacra curve outward, not inward, as they do in the smaller 

 specimen. These differences may be only a matter of variation, but this 

 large specimen is probably a distinct species. As I have noted these 

 characters mainly on the photographs and have not the specimens before 

 me, I hesitate to describe it as a new species and therefore leave it where 

 Cotteau placed it, under antillarum. 



The small size, ovate or obovate form, and almost perfectly trans- 

 verse anterior pair of ambulacra distinguish this species from other 

 West Indian fossil species of Eupatagus. 



Eocene, St. Bartholomew limestone, St. Bartholomew, Guppy collec- 

 tion ex Cleve, 2 specimens, cotypes, U. S. Nat. Mus. No. 1 15395. Besides 

 the Cleve collection, Cotteau mentions having specimens from the 

 museums of Stockholm and Upsala. 



1 By clerical error, Cotteau, in his text (p. 43), refers this species to plate 7, figures 7 to 11, 

 which should read, figures 8 to 12. Similarly, in his description of the figures, each figure referred 

 to is one number too low; figure 7, side view, should read, figure 8, side view, etc. The legend 

 on the plate is correct. 



