126 Dr. T. Wright on a new Genus of Fossil Cidaridse, 



large, anal rim prominent ; mouth-opening small ; peristomc 

 decagonal, nearly equal-lobed. 



Locality. Cornbrash, Wiltshire. 



Coll. British Museum, from Dr. Smith's collection ; Dr. Wright. 



Hemipedina tuberculosa, Wright, nov. sp. 



Test elevated, subconoidal ?, the precise form unknown ; ambu- 

 lacral areas with two rows of basal semitubercles raised on 

 very prominent bosses diminishing rapidly in size into coarse 

 granules above ; interambulacral areas with two rows of large 

 tubercles set on very prominent bosses, with scrobicular circles 

 of coarse granules surrounding the areolas ; two rows of small 

 secondary tubercles close to the poriferous zones from the 

 peristome to the equator, and three or four at the base of the 

 intertubercular space ; upper surface enveloped in the matrix ; 

 apical aperture large. 



Locality. Coral Rag, Wiltshire. 

 Coll. British Museum. 



Foreign Species of the genus Hemipedina. 

 Hemipedina seriale, Wright. 



Diadema seriale, Agassiz ; Leymerie, Mem. de la Societd Geologique 

 de France, tome ii. p. 330. pi. 24. fig. 1, 1839 ; Agassiz and 

 Desor's Cat. raisonne des Echinides, 3 scr. tome vi. p. 348. 



Test hemispherical, subglobose above, flat below; ambulacral 

 areas with two rows of tubercles nearly as large as those of 

 the interambulacra ; interambulacral areas with six rows of 

 tubercles abreast at the equator, diminishing to four and two 

 rows above ; a few secondary tubercles unequally distributed ; 

 mouth-opening small ; peristome slightly decagonal. 



Locality. Inferior Lias, France. 

 Coll. M. Michelin. 



Hemipedina Woodwardii, Wright. 



This species occurs in the Cornbrash of the Marquise, near 

 Boulogne-sur-Mer. In one of the specimens before us the spines 

 are preserved ; the primary spines are not very long, scarcely the 

 length of the diameter of the test; the secondary spines arc 

 short and needle-shaped ; the surface of both kinds is covered 

 with fine longitudinal lines. 



Locality. The Cornbrash near Boulogne-sur-Mer. 



Coll. British Museum. 



