OF WESTERN SIND. 325 



occupying nearly the whole of the actinal surface, its margin being round and tumid 

 and confluent with the margin of the test. The ambulacral grooves are feebly defined 

 and do not extend to the margin. 



The peristome is unknown. The periproct is very small, and its distance from the 

 margin is nearly twice its own diameter. 



Bemarks. This species is readily distinguished from its congeners by the broad 

 petaloid ambulacra, by the slightly-convex abactinal surface, the thick and tumid 

 margins, the deep and widely-concave actinal surface, and the widely-spaced scrobiculate 

 tubercles. 



Dimensions. Length 61 millim., breadth 55 millim., height 17-18 millim. The 

 large example drawn in Fig. 9 is imperfect in length and height ; its greatest breadth 

 is 65 millim. 



Locality. In the Gaj series of strata : A few miles south of Pir Mangal (Mugger 

 Peer). Survey-number G ^5^1^. 



Illustrations of the Species in Plate L. 



Fig. 7. Abactinal view of a small test : natural size. 



8. Longitudinal profile of the same : natural size. 



9. Actinal view of a larger test: natural size. 



4. Cltpeastee complanatus, Duncan & Sladen. Plate L, Figs. 10 & 11. 



Marginal contour subpentagonal, with the three anterior angles confluently 

 rounded so as to form an arched or almost semicircular anterior margin ; whilst the 

 posterior angles are rather flatly truncate in their rounding. The length is greater 

 than the breadth in the proportion of 1 : 0"911, and the greatest breadth is opposite 

 the extremity of the antero-lateral petals ; the lateral sides are straight and converge 

 as they proceed backwards ; the posterior extremity is not incurved but nearly straight, 

 faintly undulating on account of a slight convexity in the median interradial line, on 

 either side of which there is a very slight concavity. The general form is flat and 

 depressed, with the margins thin, and the abactinal surface sloping from the very 

 slightly elevated apex at a low angle of declivity, the lines of slope as seen in profile 

 being almost straight, and the apex is consequently feebly conical or peak-like. 



The apical disk is central. The ambulacral petals are moderately long and wide, 

 petaloid, with a comparatively straight appearance, in consequence of their length and 

 the rather abrupt rounding at the outer extremity ; the zones do not close, and the 

 areas of the petals are not tumid. The paired petals are subequal in length, and the 

 odd anterior petal is a little longer. The greatest width of the paired petals is about 

 midv^ay between the extremities and is proportional to the length as 1 9 : 44, the actual 

 dimensions of the postero-lateral petal in the example under notice being 22 millim. 

 long and its greatest breadth 9-5 millim. The poriferous zones are very wide and the 

 breadth increases up to within 7 or 8 pairs of pores from the extremity, when it 

 diminishes to form. the rounding of the petal, and the posture of the pairs of pores in 

 relation to the zone becomes at the same time more oblique. The inner pores are 



