42 FAUNA OF BALUCHISTAN. 



continuity of the ribs is interrupted by them, and single parts of the radiating rib 

 are raised into short foliaceous spines. 



Locality and strafigraphical position. — Mazd,r Drik, horizon 8; Beji valley. 



RemcMfhs. — It is with hesitation that I include the above species among the 

 genus Sinnites, because it seems that neither valve was provided with ears. It is 

 unfortunate that none of the specimens exhibits the inner side of the valves, since 

 its characters, particularly those of the binge, would have been of particular value 

 in reference to the generic position of this species. In fact, it is quite possible, 

 to judge from the irregularly bent valves and the apparent absence of ears, that 

 this species should be included among the family Fiacunidce instead of Peclinidce. 



2. Genus : VOLA, Klein. 



VoLA. QUiNQUEANGULARis, spec. nov. PI. X. fig. 3-3a, 4-4a. 



The shell attained only a small size apparently, as none of the specimens ex- 

 ceed 26 mm. in height. The right valve is triangular in shape, somewhat higher 

 than long, and strongly inflated ; the umbo is short, pointed, and somewhat in- 

 curved. The ornamentation consists of five strong, high, and moderately rounded 

 radiating ribs, of which the central one is usually stronger than the lateral ones 

 which are separated by broad, somewhat concave, interstices. The whole surface is 

 also covered with numerous, regular, fine radiating ribs, which seem to be composed 

 of a broader central and two fine filiform lateral parts. The radiating ribs are 

 crossed by very closely set, fine, undulating concentric ' strise, which are 

 easily worn off by weathering. The ears are small and were apparently unequal 

 the anterior one being the larger. The left valve is very imperfectly known but it 

 is apparently slightly concave, exhibiting a similar shape to the right valve. 



Locality and stratigraphical position. — D^s valley. 



Bemarks.— This species is so closely related owing to its general shape and 

 ornamentation to Tola (Janira) sexangularis, d'Orb., that it is only distinguished 

 by the smaller number (5) of principal ribs. 



Vol A QTJADRicosTATA, Sowerby sp. PI. XI. fig. 5, 6-6b, 7.7b. 



1814. Peoten guadrioostatus, Sowerby, Min. Con., Vol. I, p. 121, pi. 56, figs. 1 and 2. 



It would be superfluous to describe this well known species in detail; but a few 

 remarks as to the peculiar features of the ornamentation will not be out 

 of place. The difference in strength between the principal and intermediate ribs 

 becomes in some specimens somewhat effaced, particularly when the left valve has 

 attained some size, but at the same time the principal ribs remain always dis- 

 tinguishable. The number of intermediate ribs on the left valve is invariably three ; 

 there is not a single specimen which shows any deviation from that number 



