with a Synopsis of the Species included therein, 99 



C. Species from the Great Oolite and Cornhrash. 



Hemipedina Davidsoni, nov. sp. 



Test much depressed, 1 inch in diameter ; ambulacral areas with 

 two rows of marginal tubercles very regular in their arrange- 

 ment throughout ; interambulacral areas wide, with two rows 

 of primary tubercles, fourteen in a row, and two rows of 

 secondary tubercles which extend beyond the equator, between 

 the former, and two rows of smaller tubercles between the 

 main rows and the poriferous zones, so that at the equator 

 there are six rows of tubercles abreast, whilst on the upper 

 surface there are only two rows ; mouth-opening small, in a 

 concave depression ; peristome decagonal and nearly equally 

 lobed ; apical disc absent. 



Locality, — The sandy beds of the Great Oolite, Minchin- 

 nampton. 



ColL Dr. Wright : only one specimen known. 



Hemipedina Woodwardii, Wright, nov. sp. 



Test circular, much depressed; ambulacral areas narrow, with 

 two rows of small tubercles below and extending as far as the 

 equator, diminishing to granules on the upper part of the 

 areas; interambulacral areas with two rows of rather large 

 primary tubercles, eight in a row, and two rows of secondary 

 tubercles, three to four in each row, which scarcely reach the 

 equator, the upper part of the intertubercular space being 

 filled with a small, abundant miliary granulation ; apical disc 

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

 decagonal, nearly equal-lobed. 



Locality. — Copnbrash, Wiltshire. 



Coll. British Museum, from Dr. Smithes 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. 



7* 



