OF WESTERN SIND. 195 



where there is a tendency towards rostration. The plastron and the neighbouring por- 

 tions of the test are destroyed. 



The peristome is large, very excentric anteriorly, and measures 9-5 millim. in 

 breadth (transverse diameter). It is well rounded at the sides, and there is no rim on 

 the anterior margin. The posterior margin or lip is destroyed. 



One fascicle only, which is peripetalous and well developed. It is broadest at the 

 extremity of the antero-lateral petals, touching the groove at this point. It curves 

 round and passes inward somewhat obliquely, and, diminishing gradually in thickness, 

 is then continued for a very short distance parallel with the petal, and more than half 

 the breadth of the groove remote from its margin ; before it has reached midway along 

 the petal it bends abruptly backwards, passing in an oblique line inwards towards the 

 outer third of the postero-lateral petal. On attaining the commencement of the down- 

 ward slope of the area along the margin of the petal the fasciole is again bent, and, fol- 

 lowing the outline of the petal, passes close to its posterior extremity, and thence mounts 

 immediately the high posterior keel. In front the fasciole passes from the extremity of 

 the antero-lateral petal in a straight line, directed forwards and inwards, to the summit 

 of the adjacent tumid interradial plate, diminishing in width in its course. From this 

 knob it passes in a straight line, still forwards and inwards, to the knob of the corre- 

 spondent plate on the companion column, increasing temporarily in breadth midway. 

 From the anterior knob the fasciole passes a little forwards, and crosses the anterior 

 sulcus with a forward-bending curve at a very little distance from the ambitus. 



The ornamentation of the test is remarkably handsome. It is smaller towards the 

 posterior portion of the test and within the fasciole, and increases in size at the margins 

 and on the actinal surface. It is also rather larger along the margins of the ambulacral 

 grooves than on the other portions of the interradia circumscribed by the fasciole. Just 

 above the ambitus in the anterior interradia, where the ornamentation is well developed, 

 it consists of large primary tubercles, with a small perforate mamelon on a low and 

 coarsely crenulated boss, standing on a large, circular, scale-like scrobicule, the aboral 

 half of which is prominent, whilst the adoral merges imperceptibly into the substance 

 of the test. A single row of small, well-spaced, and equal-sized miliaries surrounds the 

 scrobicule; and additional ones may be present on the actinal surface, where the 

 tubercles and their scrobicules are larger and more widely spaced. 



Bemarks. This species has much resemblance in form to some of the species of the 

 genus Linthia ; but it is clearly a Hemiaster, in possessing only a peripetalous fasciole, 

 portions of the test which would be traversed by the latero-subanal fasciole, if present, 

 being well preserved. 



Dimensions. Length of the test 65 millim., breadth 60 millim., height 37 millim. 

 (or probably somewhat greater). 



Locality. In the Khirthar series of strata : Gorge of the Baran river, north-east of 



Bula Khan's Thana. Survey-number ^?|?. 



