OF WESTERN SIND. 29 



contour ; it is ornamented on its surface ; and the sutures are usually punctured with 

 isolated pits. There is a single suranal plate, placed in such a manner that a line 

 drawn through its centre and the middle of the peiriproct ireaches the other side of 

 the anal ring and traverses an ocular and not a genital plate. 

 The species are Cretaceous, Eocene, Miocene, and Recent. 



1. Salenia Blanfoedi, sp. nov. Plate VI, Figs. 1-8. 



The test is large, depressed, broader than high, flat at the abactinal surface, and 

 narrower and slightly incurved at the actiual part, and convex at the ambitus. 



The apical system is small, does not reach nearly to the edge, where the test 

 becomes suddenly convex ; it projects very slightly at the suranal plate, and is pen- 

 tagonal or obscurely circular in outline. The anal opening is large, and is surrounded 

 by a raised ring, which is highest where it is formed by the edge of the suranal 

 plate, and lowest where the first ocular plate enters into its composition. The shape 

 of the opening is an irregular oval. The madreporic genital plate (plate no. 2), irre- 

 gularly triangular in shape, is smallest externally and broadest internally ; it is of 

 about the same dimensions as the third and fourth generative plates, being very 

 slightly the larger. Its margins, like those of the other apical plates, are deeply and 

 sparsely indented, and its generative pore is in the outer third ; the small madreporic 

 pit is raised and nearly central, and there is some minute pitting also. The plate 

 does not reach the anal orifice, and is in contact with the generative plate on either 

 side and with the suranal plate. The left anterior generative plate (the third) 

 resembles the madreporic in its contour ; it is flatter, and the pore is large. It 

 touches the generative plates on either side, and joins the suranal by a dentate 

 suture like the madreporic. The next plate in succession (the fourth) is of the same 

 shape as those just noticed ; and it is in contact with the suranal plate, but it does 

 not enter the anal ring. The posterior generative plate (the fifth) is broad within, 

 where it forms part of the anal ring, and small and pointed externally ; it is shorter 

 and broader than the others, and is unsymmetrical. Its pore is large and at the base of 

 the ring. This plate is in contact with the plate just described (the fourth) and with 

 the ocular plate which enters the anal system, and with the posterior edge of the 

 suranal plate. The first generative plate resembles the fifth, and forms part of the 

 anal ring ; it is in contact with the suranal plate, and with the ocular plate (no. 1), 

 and it is also in contact with the madreporic plate and the ocular plate (no. 2). 



The ocular plates are wide and short from within outwards ; they are curved 

 within, and straighter without, with a projection pointing to the median line of the 

 ambulacrum. They are subequal ; but the first plate, the right posterior, is curved 

 externally and broad within, and it enters into the composition of the anal ring, being 

 united to a generative plate on either flank. The suranal plate is small, and may be 

 slightly or decidedly smaller than the madreporic plate ; it is indented at the orifice, 

 where its margin forms a moderately developed ridge projecting obliquely ; and it is 

 in broad contact by processes with the madreporic, the left antero-lateral, and the 

 left posterior lateral plates (that is, with plates 2, 3, and 4), and it touches by its 



F 



