﻿EXOTIC UNIONIDiE. 249 



remaining are quite young, being one and a half inches wide. One of them is from 

 Murray river, the other has no habitat. In general outline it is near to auratus, 

 Swain., but it is thinner and the axis minor of the ellipse is greater. 



Unio vittatus. PL 38, fig. 128. 



Testa crebre et leviter sulcata, elliptica, inflata, ingequilaterali ; valvulis crassiusculis, antice crassioribus ; 

 natibus proininentibus ; epiderniide luteo-oliva, nitida, eradiata, transverse vittata; deutibus cardin- 

 alibus subloiigis, coinpressis, obliquis ; lateralibus longis, laniellatis subcurvisque ; margarita alba et 

 iridescente. 



Shell closely and delicately sulcate, elliptical, inflated, inequilateral ; valves a little 

 thickened, thicker before ; beaks rather prominent ; epidermis yellowish olive, 

 shining, without rays, transversely banded ; cardinal teeth rather long, compressed, 

 oblique ; lateral teeth long, lamellar and somewhat curved ; nacre white and 

 iridescent. 



Unio vittatus, Lea. Proc. Acad. Nat. Sci., 1859, p. 153. 



Rob. — Australia. H. Cuming. 



My cabinet and cabinet of Mr. Cuming. 

 Diam. '9, Length 1-7, Breadth 2'5 inches. 



Shell closely and delicately sulcate, elliptical, inflated, inequilateral ; beaks rather 

 prominent; substance of the shell a little thickened, thicker before ; ligament long, 

 rather narrow and brown; epidermis yellowish olive, shining, without rays, trans- 

 versely banded at the somewhat distant lines of growth ; umbonial slope raised and 

 rounded; cardinal teeth rather long; compressed, oblique, double in the right and 

 single in the left valve ; lateral teeth long, lamellar and somewhat curved ; anterior 

 cicatrices rather large and confluent ; posterior cicatrices large and confluent ; dorsal 

 cicatrices placed in a row across the cavity of the beaks ; cavity of the shell rather 

 deeply excavated and rounded ; cavity of the beaks very shallow and rounded ; nacre 

 white and iridescent. 



Remarks. — There are two specimens before me, the larger one much the more 

 perfect, and from it the figure is made. This belongs to the cabinet of Mr. 

 Cuming. The inferior one is smaller and much eroded at the beaks, and consequently 

 somewhat thrown out of its normal outline. This Mr. Cuming kindly permits me to 

 place in my cabinet. On both of these the well marked lines of growth form a 

 striking character, being dark brown and very regular. On the more perfect speci- 

 men these are further apart and more distinct. The beaks not being perfect in either, 

 the character cannot be given, they may be slightly undulate at the tip. In outline 

 this is near to Gambodiensis, (nobis), and Mauritianus, (nobis), but it is much larger 

 than either, and is a thinner shell than the former and a thicker one than the latter. 



