41. 
CRETACEOrS ECIIINODERMATA 
In the cretaceous rocks of South India we hare three representants, only one of 
■\vhich, however, admits of a sufficiently recognisable characteristic being given. 
They arc all from the uppermost beds of the cretaceous series, the Arrialoor 
group. 
1. PsEUDOniADEilA SEBANGELATEM, StoUczlca. PI. VI, Pig. 8. 
Ps. testa rotundate suhpentagona, amhulacris ad periplieriam paulo projicienti- 
biis, vedde depressa, supra deplanata, infra lente convex'mscula ; hihercuUs in areis 
ambidacraUhiis biserialibus, alteris couspicuiter majoribus, in interambnlacris six- 
serialibus, seriebus duabiis internis maximis, externis miilto minoribus, hand usque 
ad marcfinem apicalern conlinuis, omninis crennlatis, mammilUs depresse globosis 
atque perforatis iustructis, interspaciis undique minute granulatis ; zonis poriferis 
infra et ad peripheriam bigeminatis, regularibus, supra versus margineni apicalern 
alternantibus, rare trigeminatis. Area apicaU magna,pentagona ; apertura mediocri, 
rotundata ; alliludine testce circa tertium partem diametri eequante. 
This species appears to have its closest ally in the European Ps. variolare, Cott., 
from Cenomanien beds. It is, however, readily distinguished from it by its distinctly 
pentagonal shape, a wider apical opening, and by the three rows of tubercles on 
c'aeh series of interambulacral plates being better developed. The outermost of 
these rows on cither side is composed of the smallest tubercles, which disaj)pear 
shortly after they reach the upper surface of the test above the periphery ; the 
next row of tubercles on cither side reaches very nearly, and the two median rows 
fully to the apical margin ; the last are also parallel to each other, while in Ps. 
variolare the tAvo median rows arc divergent and the two outer ones much shorter. 
The ambulacral tubercles are prominent, and slightly larger than any of the 
interamlmlacral ones. The interspaces are finely granular. There is no essential 
difference in the poriferous zones, on the upper side of which the pairs of pores 
are alternating, and very closely following each other. The apical disc is lost in the 
single specimen, but the opening is rather a large one, pentagonal, slightly longer 
than broad. The aperture is also moderately large and rounded. 
Locality. — Karapaudy ; a single specimen in a whitish sandstone. 
Fo rma t io n. — Arrialoor group . 
2. PSEEDODIADEMA sp. indet. PI. VI, Fig. 9, and PI. VII, Pig. 1. 
A single specimen in the collection evidently belongs to a peculiar, highly 
ornamented species, of a somewhat depressedly hcmisjAherical shape above, and 
slightly rounded beloAV, but it is so imperfect that no reliable characteristic can be 
draAvn up by which the species could again with facility be recognised, 
i 114 ) 
