258 THE FOSSIL ECHINOIDEA 



3. Cltpeaster monticulifera, Duncan & Sladen. Plate XL, Figs. 3 & 4. 



A Clypeaster, elliptical in shape, with a decided boss in the position of the apical 

 system, and subequal widely open ambulacra, and a concave actinal surface. 



Locality. Nari series. West side of Bhagothoro Hill, south of Sehwan. Survey- 

 number G ^7^. 



Illustrations of the Species in Plate XL. 



Fig. 3. The test, from above. 

 4. Longitudinal outline. 



Suborder ATELOSTOMATA. 

 Family CASSIBULIDJE. 



Subfamily ECHINOLAMPINM. 



Genus ECHINOLAMPAS, Gray, 1826. 



The Nari series contains many species of this genus, and some are small and others 

 are large forms. Although depressed in height, these last cover in some instances a 

 greater area than any hitherto known forms. 



1. EcHiNOLAMPAS DiFFiciLis, Duncan & Sladen. Plate XL, Figs. 5-7. 



The test is irregularly oval in outline, rounded in front, broader behind the 

 antero-lateral ambulacra than in front of them, broadest at about two thirds of the 

 length from the posterior zone of the antero-lateral ambulacra to the anterior zone of the 

 posterior ambulacra, and it narrows thence to the median line behind, being slightly 

 nipped-in. The margins are rounded, tumid in front and at the sides, and become 

 thinner at the posterior ambulacra and behind. 



The test is rather low, has its highest point nearly central, and slopes gradually 

 and very nearly equally to the front and backwards. 



The apical system is slightly excentric in front, about one fifth of the whole length ; 

 it is on the anterior slope of the test. The disk is large, the pores of the anterior 

 basals (generative pair) are closer together than the posterior, and the madreporic 

 body is broad behind. 



The petals are rather blunt at the apex, are long, with slightly sunken poriferous 

 zones and faintly tumid interporiferous areas. They show very slight indications of 

 closing, and are unequal in size. 



The anterior ambulacrum, the shortest and slightly the narrowest, is lanceolate in 

 outline, and the poriferous zones keep widely open to the end. The right zone (a) is 

 the shorter of the two. As is the case with the other zones, they are narrow and about 

 one half of the breadth of the interporiferous area. The pores are large, the inner 

 are smaller and circular in outline, and the outer broadly and elongately comma- 

 shaped. They are in a wide groove, and each pair is separated by a well-developed 

 costa carrying a row of small miliaries. 



