8 
CRETACEOUS ECIIINOEERMATA 
6. EciimoUEiD.'E, poriferous zones complete, meeting at the apex ; peristome simple, angular ; 
no jaws? (including the Caratomince as suh-family.) 
7. Eysasterid^, poriferous zones complete, meeting above in two separate points, (anteriorly 
as trivium, posteriorly as hivium ) ; jaws absent. 
8. Clypeastrid/E, poriferous zones jietaloid, five genital plates, jaws jmesent. 
9. C4S«/£)ra/£i.i’, poriferous zones sub-petaloid, all superiicial, ambulacra not depressed, generally 
four genital plates ; mouth central or excentric, round or pentagonal ; peristome often with tubercles 
round it. 
9a. Cassidulina, wdth anal opening situated superiorly terminal, in a groove; pores in all 
zones similar. 
%. Ec/iimlampince, with. i\\Q nwai opening inferiorly marginal, notin a groove ; pores in all 
zones similar. 
9c. Claviaslerina, anus inferior, sub-marginal, pores in the anterior ambulacrum somewhat 
dilfei’ent from others. 
10. Spatargieje, some of the ambulacra with the suh-petaloid poriferous zones excavated, 
mouth excentric, transversely oval, bilabial. 
10a. Ananchiiina, only the anterior ambulacrum generally depressed; apical disc elongate. 
lOi. Spaiangina, all ambulacra lie in depressions; apical disc concentrated. 
Oat of these ten families, seven are represented in the South Indian cretaceous 
deposits, hut mostly only a few species occur in each. 
Eollowing the groups as above arranged, there is a gradual change ol)servahle 
from, the purely actinoid or radial to the bilateral type, which is most developed in 
the Spataxgii).'E, and according to the arrangement previously adopted in the 
present series of monograplis of South Indian cretaceous Invertehrata, I shall begin 
the detailed account with the last-named family. The distribution of the species 
in the different geological groups, as presently distinguished, will be noticed subse- 
quently in a few general remarks on the subject. 
In conclusion, I may just allude to a short paper on the classification of the 
Echinoidca by M. Pomel, published in the Comptes llenchis for August 1SG8, p. 302. 
This paper is an abstract from the author’s introduction to the Tertiary Echinoidea 
of Algiers. M. Pomel proposes to divide the order into three divisions, Spatifornies, 
Lampadiformes and Glohiformes. The first are typified by the Spatangip.e, the 
second by the Cassidulipje, and the third by the Cidaridje. Although the author is 
strongly of opinion that these divisions are considerable improvements rxpon the 
classification now more generally in use, it appears to me that his Auews are based 
upon the examination of only a limited number of forms from rather recent deposits, 
without much regard to the older representants of the order. 
Family— Sr A TANG IB jF. 
Desor, Syuop. Echiii. foss., p. 327. 
The members of this family usually have a cordately ovate, more or less 
elevated test, with the anterior ambulacrum difierently developed from the rest, and 
generally situated in a groove ; the others are more or less distinctly petaloid ; the 
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