178 



Var. candaharica (Hanley $ Theobald) ; Simpson, Washington, 

 D.O., Smiths. Inst., Nat. Mus. Proc. xxii, 1900, p. 855. 



Unio marginalia var. candaharica, H. & T., C. I. 1876, p. 20, pi. 43, 

 fig. 4 ; Hutton, J. A. S. B. xviii, pt. 1, 1849 (1850), p. 660. 



Original desertion: Shell oval oblong, ventricose, tumid 

 not produced nor attenuated behind ; beaks flattened and denuded ; 

 upper edge rounded or falling ; lower edge curved ; strongly- 

 wrinkled transversely ; epidermis olive-brown, in young specimens 

 with broad yellowish margin. 



The dimensions of three specimens mentioned by Hutton 

 are : 



1. 3. 



Long 41-25 41-25 44-25 mm. 



Lat 75 73 78 mm. 



and of two specimens, both from Candahar, in the Indian 

 Museum : 



1. 2. 



Long. , 37-5 38-25 mm. 



Lat 65-5 68-5 mm. 



Diam 22-5 24-5 mm. 



Hob. Candahar, in canals. 



Hutton further states that it differs from typical U. marginalis, 

 Lk. " in the less produced and lengthened form pos- 

 teriorly, in the upper part of the anterior edge being straighter 

 and more elevated than in U. marginalis, and in the beaks being 

 less denuded and more wrinkled. In Unio marginalis of the 

 Gangetic Provinces the breadth appears to exceed the length 

 much more considerably than in the Candahar shells, measuring 

 in four specimens of each as follows : 



" Indian [Gangetic Provinces] specimen, 



1. 2. 3. 4. 



Long 35 41-25 35 38 mm. 



Lat 40 89 80 76-5 mm. 



"Afghan specimens, 



1. 2. 3. 4. 



Long *. . 16 41-25 41*25 46 mm. 



Lat 75 73 75 78 mm. 



"The proportions thus appear to be reversed; the Indian 

 species showing a greater transverse breadth in proportion to its 

 length, the Afghan one showing a greater length in proportion to 

 its breadth. All my specimens of the Indian variety are produced 

 or elongated posteriorly, giving the shell a narrow wedge-shaped 

 appearance, whereas the Afghan one, being transversely shorter, 

 appears ovate-oblong." 



