OF KACHH AND KATTYWAR. 69 



the margin, consists of a small group of tubercles near the groove, and of a linear series 

 extending below the line of the antero-lateral ambulacrum. 



The lateral interradia are marked with some twenty large tubercles of the same 

 character as those of the anterior interradials ; they vary somewhat in size, and 

 the smallest are the lowest. They are in irregular rows, and the uppermost set is 

 separated from the others by the peripetalous fasciole. Occasionally some of the 

 tubercles are close to the distal end of the poriferous zone of the posterior ambulacra. 



The junction of one side of the tubercles with the test in which the scrobicule 

 is sunken is very evident ; they rise but little, or not at all, above the level of the test, 

 and have a minute mamelon which is perforate and crenulated. The ornamentation 

 between these great tubercles is very closely packed, and consists of small flat tubercles 

 larger than miliaries, with hardly any space between them. 



The posterior interradium, convex from side to side, keeled anteriorly and trun- 

 cated posteriorly, has no large tubercles upon it, and the ornamentation resembles that 

 of the other interradials. 



The peristome is transverse, slightly sunken, with a well-developed posterior lip. 

 The anterior groove, after notching the margin of the test, is lost, and does not lead to 

 the peristome. A very narrow and slightly projecting posterior ambulacrum leads on 

 either side of the plastron to the peristome in front, and to the strongly ridged arched 

 portion of the ambulacrum within the subaual fasciole behind. This narrow band has 

 no tubercles, and they are small on the ridge. 



The plastron is narrow and is covered with small tubercles on flat, raised scrobicules, 

 and their size diminishes towards the dependent projection, which is crossed by the 

 fasciole. 



The rest of the inferior surface beyond the fasciole and the plain band of the 

 posterior ambulacra is profusely tuberculate, the dimensions of the tubercles increasing 

 from the margin inwards. Usually the tubercles project from the edge of flat scrobicules 

 with circular or elliptical margins ; but occasionally the scrobicule is sunken in front, 

 and a miniature of the large tubercles of the abactinal surface is produced. 



The subanal fasciole is strongly developed, and is on the slope of a considerable 

 bent ridge placed on either side of the test. The fasciole crosses over to the opposite 

 side between the peristome and the depending part of the plastron, and forms above a 

 curve, concavity upwards, which is situated far below the anus. Within the area 

 limited by the fasciole are some pores of the ambulacra and some distinct tubercles in 

 rows ; these tubercles diminish in size towards the median line, and are placed on 

 slightly raised, flat, elliptical or circular scrobicules. 



There is a concave space below the anus, and it is limited below and at the sides 

 by the ridge for the subanal fasciole. 



There is a narrow and very sinuous peripetalous fasciole ; it can be seen passing 

 round the end of the antero-lateral ambulacra and curving upwards and forwards 

 between the series of large tubercles on the anterior interradia to cross over to the 

 opposite side. Posteriorly it passes upwards and backwards, separates the upper 



