50 PAUNA OF BALTJOHISTAN. 



Locality and stratigraphioal position. — Maz^r Drik, horizon 8. 



Bemarhs. — It is readily distinguishable from other species by its peculiar 

 ornamentation. In Boudairia cristata, Stol. sp., from the Ariyaldr series, the 

 horizontal ribs are limited to the anterior part of the valves only, and do not extend 

 as far as the keel. Boudairia drui, Mun. Chalm., is distinguished by comparatively 

 longer and narrower folds on the anterior part of the shell, but it is apparently the 

 nearest relation to the Baluchistan form. 



It is highly interesting that this genus, which up till now has only been known 

 in the upper cretaceous beds of North Africa and Southern India, should appear 

 in beds of the same age in Baluchistdn, which otherwise have hardly any forms in 

 common with the cretaceous beds just mentioned. 



B. SINUPALLIATA. 



1. Family: CEAMIDM. 



Genus : GHAMA, Linng. 

 Chama CAiLOSA, spec. nov. PI. XII. fig. 9-9a, 10-lOb. 



The shell is inequivalve, the left (?) valve considerably larger than the right (?) 

 one ; it is irregularly rounded in shape, and inequilateral. The larger (left ?) valve 

 is strongly inflated, the beak tumid, but depressed and slightly rolled in. The 

 ornamentation consists of somewhat irregular, strong, concentric and lamellous ribs, 

 which are separated by broad interstices. The smaller (right ?) valve is flat, its 

 umbo very low, depressed and slightly rolled in ; the ornamentation is similar to 

 that of the big valve, but the ribs are much more closely set, and the interstices 

 therefore less broad. 



Locality and stratigraphical position. — Maz^r Drik, horizon 8. 



* 



Bemarks. — It is rather strange that the above- described species shows no 

 particular resemblance to any of the cretaceous forms of this genus, but, on the 

 other band, bears the strongest likeness to Chama squamosa from the eocene beds, 



2. Family : EIPPURITIDM. 

 Genus : RADIOLITES, Lamark. 

 Babiolites subdilatata, Eomauowski, sp. PI. XIII. fig. 4-4a, 5-5a, 5A. 



1884. Spharulites dilatata, Eomauowski ; Material. Geol. Turkeetan, pi, XX, fig. 4 a (noni and c). 



This species is chiefly represented by internal casts of the lower valve. The shell 

 has nearly entirely disappeared in most of the specimens, and only a few fragments 

 still adhering to some specimens, permit an idea being formed as to its ornftment' 

 ation. 



