OF KACHH AND KATTYWAR. 11 



IV. Description of the Fossil EcMnoidea of the 'Nummulitic Series of Kachh. 



Order ECHINOIDEA ENDOCYCLICA. 



Family GLYPEOSTOMATA. 



Subfamily TEMNOPLEUBIDM. 



Genus ARACHNIOPLEURUS, Duncan & Sladen, 1882. 

 A solitary specimen of this genus, which was diagnosed in the " Fossil Echinoidea 

 of Western Sind " (Pal. Indica, series xiv. vol. iii. fasc. 2, p. 42), is in the collection from 

 Kachh. It is evidently a variety of the species Arachniopleurus reticulatus, Duncan & 

 Sladen, of Western Sind, from the Eanikot series, found underneath the great develop- 

 ment of Khirthar Nummulitic limestone. 



1. ARACHmoPLBUEUS BETicuLATUS, Duncan 8f Sladen, variety. Plate XI, Fig. 6. 



This species was described by us in the " Fossil Echinoidea of Western Sind " (Pal. 

 Ind. ser. xiv. vol. iii. fasc. 2, p. 42, and figured on plate ix. figs. 6, 7, 8). 



The variety differs from the type in having vertical ridges between the transverse 

 ridges of the interradia, making the ornamentation more reticulate, and in having 

 two costal ridges placed vertically below the perforate and crenulate tubercles of the 

 interradia. 



Locality. From a canon in Nummulitic rock between Maniara-Fort hill and Karray. 

 Survey-number C 050. 



Illustration of the Variety in Plate XI. 

 Fig. 6. Part of the test : magnified. 



Order ECHINOIDEA EXOCYCLICA. 



Suborder GNATHOSTOMATA. 

 Family CLYPEASTRID^. 



Subfamily EUCLYPEASTBID^. 



Genus CLYPEASTEE, Lamarck, 1801. 



A true Clypeaster, with very remarkable ambulacral developments, and possessing 

 the needle-shaped pillars near the edge of the test and between the ambulacra within 

 the test, is in the Nummulitic series of Kachh. Unfortunately the posterior part of the 

 test is absent and the apical system also. The peristome is covered with a very solid 

 mass of Nummulites. 



1. Cltpbastee apbbtus, Dwncan §(• Sladen. Plate VI, Figs. 6, 7. 



The test is oval-elliptical in marginal outline, very flat beneath, very depressed, 

 with a thin rounded-off edge, and it slopes at first very gradually from the margin to 



c2 



