FRESHWATEIl SHELLS OF AUSTRALIA. 267 



24. BiTHiNiA SoHHADERi, Fraueiifeld. 



Bithinia Schraderi, Frauenfeld, I.e. 1862, p. 1153, 1864, p. 665, 1865, 



p. 527, pi- viii. 

 Rah. Australia ? (Frfld.). 



25. BiTHiKiA HTALiNA, Bfazier. 



Bithinia hyalina. Brazier, Proc. Linn. Soc. N. S. Wales, 1875, vol. i. 



P- 9- 



" Shell turbinated, thin, glossy, ehiuing, whitish under a brown 

 epidermis. "Whorls 5, roundly convex ; the last large, equalling 

 half the lengtli of the whole shell. Aperture somewhat luaate ; peri- 

 stome thickish ; margins continuous. Length 4 lines, breadth. 2|. 



"Sab. Eastern Creek, N. S. Wales. 



" Pound in various parts of New South "Wales, about Parra- 

 matta and Chatsworth." — Brazier. 



26. Bithinia austealis, n. sp. (Plate VII. fig. 18.) 



Shell small, white, not perforate. Whorls 4-5, very convex, very 

 finely striated by the lines of growth. Suture deep, scarcely oblique- 

 Aperture small, obliquely oval, somewhat acute above, occupying 

 less than half the entire length. Peristome continuous, a little 

 prominent on the columellar side, thus producing a false umbi- 

 lical rimation and somewhat thickened, thin elsewhere. Oper- 

 culum normal, shelly. 



Length 5 millim., diam. 3 ; aperture 2^ long, 1-| wide. 



Sal. Victoria Eiver, N". Australia. 



Besides the striae or lines of growth, by the aid of a compound 

 microscope very fine transverse lines are observable. 



Under the name of B. affinis. Brazier, two specimens found at 

 Hillgrove Limestone Creek, Burdekin Eiver, Queensland, have 

 come under my observation, sent to Mr. J. Taylor of Leeds by 

 Mr. C. E. Beddome of Hobart Town, Tasmania. They differ 

 from those here described in having the last whorl smaller, the 

 increase of the volutions appears to be less rapid, and the oper- 

 culum is much more distinctly concentrically ringed by the lines 

 of growth. 



Grenus Gabbia. 



27. Gabbia austealis, Tryon. 



Gabbia australis, Tryon, American Journal of Conchol. vol. i. p. 220, 



pi. xxii. fig- 7- 

 Sab. New South Wales. 



