22 THE TERTIARY FOSSIL ECHINOIDEA 



2, EcHiNOLAMPAS ALTA, Duncan & Sladen, variety. Plate I, Fig. 7. 



Many specimens of this species are in the collection, and there appears to be but 

 slight variation in them in spite of differences of size. The main distinction (which, 

 however, is only slight) is that in some forms the test is less oval in actinal outline 

 and approaches an ellipse with one end more rounded than the other. This is produced 

 by a slight enlargement of the test close in front of the postero-lateral ambulacra 

 (Plate I, fig. 7). Again, the type has tumid interradials abactinally ; another form is 

 less tumid ; and a third, that represented in Plate I, fig. 7, is barely tumid. We feel 

 disposed to admit this last as a variety, and to characterize it by the deficient 

 tumidity of the interradials abactinally, the more ellipsoid shape actinally, and the 

 comparative shortness of the ambulacra. It is from the same locality as the type. 



Illustration of the Variety in Plate I. 



Fig. 7. EcMnolampas alta, Duncan & Sladen. Variety. 

 Actinal surface : natural size. 



A large specimen, which has been crushed somewhat from above downwards, is 

 from the same locality. It shows a slightly more prominent condition of the inter- 

 poriferous zones than the type. The curve of the postero-lateral ambulacra is greater, 

 and the shape of the base is broader. There is no doubt about the single row of 

 granules separated by smaller ones or by spaces on the costee of the poriferous zones, 

 and that the ornamentation of the test consists of sunken tubercles with mamelons and 

 crenulations, the intermediate areas being largely granular. 



One specimen is remarkable for its height, yet the specific distinction of a greater 

 breadth than height prevails. The dimensions are: length 84 millim., breadth 67 

 millim., and height 64 millim. This is the greatest deviation in point of greater height 

 from the type. Relative length to height 1 to 0-76. Survey-number C 050 B f. 



Another, and larger, specimen has the following dimensions: — length 90 millim., 

 breadth 70 millim., and height 64 millim. ; length to height 0-71. Survey-number 

 C050. 



This remarkable Echinolampad is common, and at once strikes the eye on account 

 of its height, tumid interradia near the apex, the slant behind, the vertical sides, and 

 the long gradually enlarging ambulacra. 



It resembles a Conoclypem in shape and ornamentation. There is no species like 

 it in the Tertiaries of Sind; but de Loriol's monographs of the Nummulitic deposits 

 of Egypt contain admirable descriptions and figures of very closely allied forms. 



EcMnolampas Fraasi; P. de Loriol*, is closely allied; and it is to the group of 

 which that fine African species is a type that the form from Kachh belongs— tall 

 Echinolampads, with long, not very unequal, and not petaloid distally ambulacra. 



* "MonograpMe des Echinides nummulitiques de I'Egjpte," Mem. Soc. de phys. et d'hist. nat. de 

 Creneve, t. 27, i. p. 92, pi. y. fig. 1. - Eocane Echinoideen aus Aegypten und der Libyschen Wuste," Palseon- 

 tographica, N. F. x. 1. (xxx.). p. 22, pi. vi. figs. 1, 1 a, 1 6. 



