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



B. Species from the Inferior Oolite. 



Hemipedina Bakeri, Wright. 



Pedina Bakeri, Wright, Annals of Nat. Hist. S. 2. vol. xiii. p. 312. 

 pi. 1 . fig. 4 a-c. 



Test circular, depressed ; ambulacral areas very narrow, with two 

 rows of small tubercles set so far apart that they form a zig- 

 zag row ; interambulacral areas with two rows of rather large 

 prominent tubercles, five in a row; apical disc with a pro- 

 minent anal rim ; mouth-opening large ; peristome deeply 

 decagonal. 



Locality. Pea-grit, Inferior Oolite, Crickley Hill. 

 Coll. Dr. Wright : a single specimen. 



Hemipedina perforata, Wright. 



Goniopygus ? perforates, Wright, Annals of Nat. Hist. S. 2. vol. viii. 

 p. 267. pi. 6. fig. 5a-b. 



Test small, circular and depressed ; ambulacral areas with two 

 rows of small tubercles which extend from the peristome to 

 the disc ; interambulacral areas with two rows of tubercles, 

 seven to eight in each row, three or four secondary tubercles 

 between the primary rows at the base ; surface of the plates 

 covered with numerous coarse miliary granules ; mouth-open- 

 ing large; peristome rather deeply decagonal; lobes nearly 

 equal in size ; apical disc large and foliated. 



Locality. Pea-grit, Inferior Oolite, Crickley Hill. 

 Coll. Dr. Wright. 



Hemipedina tetragramma, Wright, nov. sp. 



Test circular, -j%ths of an inch in diameter ; ambulacral areas 

 narrow, with two marginal rows of small nearly equal-sized 

 tubercles extending from the peristome to the disc ; interam- 

 bulacral areas with two rows of primary tubercles, about four- 

 teen in each row, and two rows of secondary tubercles, ten in 

 each row, extending from the peristome to nearly the upper 

 surface ; mouth-opening small, situated in a depression ; 

 peristome decagonal, unequally lobed. 



Locality. Pea-grit, Crickley Hill. 

 Coll. Dr. Wright. 



Hemipedina Waterhousei, Wright, nov. sp. 

 Test small, pentagonal, rather inflated at the sides ; ambulacral 

 areas with two rows of small tubercles extending from the 

 peristome to the disc ; interambulacral areas with two rows of 



