OF WESTEEN SIND. 217 



are very wide, and the interporiferous areas remarkably narrow, being little,- if at all, 

 wider than the divisional costse which separate the widely spaced and conjugate pairs 

 of pores. Two or three pairs of pores are aborted at the apical extremity of each zone. 

 The apical disk is excentric in front ; the ocular pores are in sunken cavities, and the 

 posterior pair are separated by the posterior extension of the madreporiform body. 

 The posterior pair of generative pores are larger and wider apart than the anterior pair. 

 The apical summit of the test apparently coincided with the apical disk ; and the pos- 

 terior slope of the test, when seen in longitudinal profile, is very slight, the posterior 

 extremity being high and thick ; the margins also are thick, and somewhat tumid for 

 this genus. The peripetalous fasciole is narrow, and was probably devoid of any sinuous 

 bend in the lateral interradia ; and there appear to be traces of a few large isolated 

 tubercles on the flanks of the ambulacral grooves. The subanal fasciole is extensive, 

 and includes seven or eight pairs of ambulacral pores on either side ; and there are 

 traces of distinct grooves radiating inwards from the pores. The actinal plastron is 

 rather prominent at the posterior peak, and its outline inward is defined as the apex of 

 a triangle by the broad posterior ambulacral areas. 



Perhaps the nearest alliances of this form are to M. Sowerbyi, from which, however, 

 it difiers by the length and character of the posterior petals, as well as by the height 

 and thickness of the posterior extremity and the margins generally ; moreover, the test 

 is much larger than that of M. Sowerlyi as at present known. 



Dimensions. From the centre of the apical disk to the posterior extremity 

 30 millim., breadth rather more than 41 millim., height 24 millim. 



Locality. In the Khirthar series of strata: Three or four miles north-east of 

 Jungshahi Eailway-station. Survey-number ^~ . 



Illustration of the Specimen in Plate XXXVI. 

 Fig. 17. Abactinal view of the specimen: natural size. 



Genus LINTHIA, Merian^^S^ZT 



(See antea, p. 17, Part i.) 



1. LiNTHiA OEiENTALis, Buncan & Sladen. Plate XXXVII, Figs. 7-14. 



Test of medium size. Marginal contour rotundly subcordiform, widely expanded 

 laterally, the breadth being slightly greater than the length, deeply indented anteriorly 

 by the anteal sulcus, contracting behind the line of greatest breadth towards the pos- 

 terior extremity, which is slightly truncate. The abactinal surface is convex, more or 

 less inflated, and deeply incised by the ambulacral grooves. The greatest height of the 

 test, which is slightly excentric posteriorly, lies on the keel of the odd posterior inter- 

 radium, and is nearly equal to two thirds of the length, or in the proportion of 0*64 : 1. 

 Seen in longitudinal profile the anterior slope is steep and rapid, the lateral interradia 

 are slightly keeled and prominent at the apex, and the posterior portion of the profile. 



