ECHINODERMATA. 289 



imperf orate mamelon. Oral opening large, with 10 deep inci- 

 sions. The apical disk not observed, but the broken opening in 

 the type specimen is large and pentagonal in outline. 



The dimensions of the type specimen are: height, 12.5 mm.; 

 width, 21.9 mm. 



Remarks. This species is the only American representative 

 of the genus so far as known, and is quite distinct from any of 

 the European forms. 



Formation and locality. Vincentown limesand, Timber Creek 

 (Clark). 



Geographic distribution. New Jersey. 



Order SPATANGOIDA. 

 Family ECHINOBRISSINAE. 

 Genus TREMATOPYGUS d'Orb. 



Trematopygus cruciferus (Morton). 

 Plate XL, Figs. 1-9. 



1830. Ananchytes cruciferus Mort., Am. Jour. $ci., ist ser., vol. 



18, p. 245, pi. 3, fig. 8. 

 1830. Ananchytes cruciferus Mort., Jour. Acad. Nat. $ci. Phil., 



ist ser., vol. 6, p. 201. 



1833. Nudeolites crucifer Mort., Am. Jour. Sci., ist ser., vol. 



23, P- 294- 



1834. Nudeolites crucifer Mort., Synop. Org. Rem. Cret. Gr. 



U. S., p. 75, P 1 - 3, % 15- 



1855. Trematopygus crucifer d'Orb., Pal. Franc., Terr. Cret., 

 vol. 6, p. 387, pi. 953, figs. 10-11, pi. 963, figs. 1-5. 



1859. Nudeolites crucifer Gabb, Cat. Inv. Foss. Cret. Form. 

 U. S., p. 19. 



1864. Nudeolites crucifer Meek, Check List Inv. Foss. N. A., 

 Cret. and Jur., p. 2. 



1868. Nudeolites crucifer Con., Cook's Geol. N. J., p. 377, fig- 

 ure; p. 722. 



1870. Nudeolites crucifer Credner, Zeitsch. d. Deutsch. Geol. 

 Gesell., vol. 22, p. 217. 



19 PAL 



