ECHINOIDEA. 



139 



No. 433. Echinobrissus (Nucleolites) cunucularis, Blaiuv. 

 Lower Oolite, Youne, France. 



No. 424. Echinolampus afl&nis, Desm. 

 Eocene, Vaiie;irard, France. 



No. 425. G-alerites albogalerus, Lam. 



This lofty, almost turreted form, with central 

 mouth and marginal anus, is from the Upper Chalk, 

 Kent, England. 



No. 426. Hemicidaris intermedia, Fleming. 



This large, depressed genus belongs to the Cidari- 

 dce with narrow ambulacra. The distinctive feature 

 is the existence of small tubercles on the lower half 

 of the ambulacra. The spines are cylindrical and 

 finely striated. From the Oolite of Calne (Wiltshire), 

 England. 



No, 427. [842, Cast]. Hemipneustes radiatus, Agass. 



This is a heart-shaped, inflated Urchin, as 

 high as broad, and nearly perpendicular in 

 front, where there is a deep, narrow furrow. 

 The ambulacral summit is central; the ambu- 

 lacra are very large and winding; the tubercles 

 small, and the anus is on the posterior bor- 

 der. From the Upper Chalk of Maestricht, 

 Holland, and now in the Ward Collection, 

 University of Rochester. 



No. 428. Micraster cor-anguinam, Agass. 



This genus is so termed from the star-like ar- 

 rangement of its four small ambulacra. The 

 test is heart-shaped, and wider before than be- 

 hind, with a furrow in front; the tubercles are 

 small, and irregularly distributed; the mouth is 

 transverse, situated anterioily, and protected by 

 a projection of the odd inter-ambulacrum. From 

 the Upper Chalk, Kent, England. 



