OP SOUTIIEPtN INDIA. 
21 
narro’o'ly truncate, and sloping inwardly l)elow tire rounded anus. The cheeks are 
eonvex; the aperture is roundly oval; the post-oral space sub-triangular, flat ante- 
riorly and very narrow at the lip, slightly elevated towards the anal end. The upper 
surface is covered with very minute granides and fine tubercles, and the lower is 
coarsely tubercular between the granules, except towards the hinder end of the 
post-oral area. 
The ambidacra arc slightly impressed and somewhat flexuous ; the antero-laterals 
diverge under an angle of 122 degrees, the postcro-laterals under an angle of about 
53 degrees, but at the base they actually diverge under a much larger angle ; the 
former have 3G pah’s of pores in each scries, the latter about 30 in tlie anterior and 
2G in the posterior zone ; the pairs arc separated by granules ; in all cases the pores 
continue to remain traceable on the ambulacra, although further on they become 
less distinct and more distant. The genital plates have very large openings, the 
anterior left is the smallest, the madrcporlform one the largest, the two lower ones 
arc wider apart and narrowly in contact. 
Localities. — South-West of Mulioor in a ferruginous sandstone. East of 01a- 
paudy in a sandy oolitic rock ; very common at both localities ; rarer in the neigh- 
bovu'hood of Karapaudy and East of Scrdamungalnm. 
Formation . — Arrialoor group; apparently a very characteristic fossil of this 
division of the cretaceous beds. 
III. Genns. — CAPtDIASTEIl, Forbes, 1850. 
Test cordiform, moderately convex ; ambulacra unequal ; anterior sulcus dis- 
tinct, margined by more or less strongly angulated edges ; lateral ambulacra open, 
the pores composing the posterior pairs in each scries often larger than the anterior ; 
apical apparatus ovate, elongate, composed of foiu genital and five ocular plates, 
the two anterior genital plates in advance of the junction of the antero-lateral 
ambulacra ; surface more finely tubcrculated and gramdar above than below, but 
generally with some enlarged tubercles along the edges of the anterior sulcus and 
about the apex ; aperture transversely kidney-shaped ; anus posterior, vertically 
ovate ; a lateral fasciolc passing all round near the lower periphery is said to be cha- 
racteristic, but it is not always distinctly marked. 
This genus was proposed by Prof. E. Eorbes for the well-known C. ananchytis, 
(Leske), (= C. granutosns, Goldf.), and is easily distinguished by the above-noticed 
characters from both Hotaster and Hemipne^istes •, the latter shows a similar inequal- 
ity in the size of the ambulacral pores, but it has the granulation of the sm’face 
equal, and does not possess a lateral fasciole. 
All the species of Cardiaster as yet known are from cretaceous beds ; two occur 
in the uppermost beds of South Indian cretaceous deposits, and both are new to 
science. 
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