OF WESTERN SIND. 251 



often great irregularity in the direction of the furrows, and they then stretch across 

 the median line and appear to merge into those of the opposite plate. The small 

 tubercles around the scrobicular margin are distant, and have their mamelon elongate 

 in shape and low. On the ambulacral side of the scrobicular margin there is con- 

 siderable space, and it is occupied by furrows and ridges similar to those of the opposite 

 side, but they are shorter ; they are longer, however, than in C. Vermuili. The coronal 

 plates are much broader than high, and they are separated from those above and below 

 by a decided sutural furrow and by the small tubercles of the scrobicular margin. 

 Moreover the scrobicular spaces of the great tubercles are just separated by the 

 furrow and the thin line of small tubercles. There are ten or thirteen pairs of 

 pores in relation to each coronal plate, and the ridges and furrows come close to 

 them from the scrobicules. Some of the pairs are conjugate, others are not. It 

 appears that there is a minute miliary granulation upon the interporiferous zones, and 

 that it is carried on to the structure between the pores. 



The dimensions of the specimens is about— breadth 62 millim., height 32 millim.? 



Locality. Nari series, Oligocene of Sind. Hindi Hill; Trak Hill. Survey- 

 numbers G ^6^7^, G ^8-1-- 



lUustrations of the Species in Plate XXXIX. 



Fig. 1. Side view of the test. 



2. A coronal plate and part of an ambulacrum : magnified. 



Family ABBACIABM. 



Genus CGELOPLEURUS, Agassiz, 1840. 



Small Urchins more or less depressed, sometimes a little elongate ; with a thin 

 test and simple pores. Tubercles neither crenulate nor perforate. Peristome small 

 and slightly incised. Larger interambulacral tubercles disappear before reaching the 

 abactinal surface, only secondary .tubercles reaching the apex in some species, so that 

 the interradia, above, resemble smooth bands which are often highly ornamented. The 

 ambulacra project and have two rows of tubercles. 



1. CffiLOPLEURUS EQUis, Agassiz. Plate XXXIX, Figs. 3-8. 



D'Archiac and Haime [op.cit.-^. 198) describe Coelopleurus coronalis, 'KXem, 

 from the French Nummulitic, as a species found in the " Chaine d'Hala." This species 

 has the synonyms of C. equis, Agass. [Catal. Syst. p. 12), and C. nitidus, Konig, sp., 

 and is characterized by the presence of a single row of secondary tubercles smaller 

 than the primaries extending along the flanks of the poriferous zone of the ambulacra 

 from the apex to the peristome ; they are small abactinally, and increase in size at the 

 ambitus. The ambulacra project considerably. 



