198 Dr. T. Wright on some new species of Hemipcdina.' 



times the width of the ambulacra], with six rows of tubercles 

 at the equator, each plate supporting three nearly equal-sized 

 tubercles abreast ; bosses prominent ; areolas surrounded by 

 incomplete circlets of small granules. 



Spines refen-ed to this species long, round, slender, and sculp- 

 tured with delicate longitudinal lines ; articulating cavity small, 

 with a smooth rim; head thick, with a thin prominent finely 

 milled ring ; body long, much more slender than the head. 



Localitij. — Kimmeridge clay, Hartwell, Bucks. 



Coll. Professor Morris. 



Hemipedina Cunningtonii, Wright, nov. sp. 



Form unknown, upwards of an inch in diameter; ambulacral 

 areas wdth two marginal rows of very small tubercles rather 

 irregular in their mode of arrangement ; poriferous zones 

 nearly straight ; interambulacral areas three times the width 

 of the ambulacral, with two row^s of tubercles situated on the 

 zonal half of the tubercular plates, leaving thereby a wide in- 

 tertubercular space which is filled with 8 to 10 rows of small 

 granules; the bosses large and ])rominent, and the tubercles 

 of a proportionate size ; areolas surrounded by a complete 

 circlet of small granules the same size as those filling the 

 middle of the areas. 



Locality. — Kimmeridge clay near Aylesbury. Collected by 

 Professor Morris. 



Coll. British Museum. 



Foreign Species from the Kimmeridge Clay. 



Hemipedina Bouchardii, Wright, nov. sp. 



Test large, depressed; ambulacral areas with two rows of re- 

 gular marginal tubercles extending without interruption from 

 the peristome to the apical disc, and separated by a median 

 zigzag line of small granules; poriferous zones straight; inter- 

 ambulacral areas three times the width of the ambulacra!, with 

 ten rows of tidjcrcles at the equator, each tubercular plate hav- 

 ing five tubercles abreast ; areolas surrounded by circlets of 

 small granules; spines slender, sculptured with longitudinal 

 lines. 



Dimensions. — Transverse diameter 2yj inches ? 

 Locality. — Kimmeridge clay, Boulogue-sur-Mer. Collected 

 by M. Bouchard Chantercaux. 



Coll. M. Bouchard Chantercaux at Boulogne. 



In the present state of our knowledge it would be premature 



