92 On the Fresh-water Shells of India. [Feb, 



I mention this circumstance, because Mr. Benson has said in No. 13 

 of the Glanings in Science, when speaking of Melanise, " I have never 

 met them in jheels or standing waters, so that they may be strictly 

 called fluviatile." 



I have not yet had an opportunity of procuring any of these shells 

 alive, from rivers : the only two living specimens in my collection were 

 taken — the one from a muddy nullah, the other from a well. 



No. 17 — Lymn.ea. 

 Shell thin, fragile, diaphanous. 



Found in abundance in the Jegu nullah at Chunar, also in most 

 jheels. 



Fresh-water Bivalves. 

 No. 18.— Unio? 

 Found in nullahs at Chunar ; also in tanks. Length of my largest 

 specimen 2| inches ; epidermis greenish brown ; beaks decorticated. In- 

 terior, beautifully nacreous. 



No. 19.— Unio? 

 Found at Chunar in nullahs and tanks. Beaks decorticated ; epider- 

 mis dark-brown. These shells are generally tuberculated interiorly, pre- 

 senting an appearance of small pearls. The pearly texture of the inte- 

 rior is often coloured with a pinkish tinge. 



No. 20.— Unio? . 

 In rivers, nullahs, and tanks. Plentiful in the Jegu nullah at Chu- 

 nar. Epidermis yellowish or pale brownish green. Beaks naked. 

 More solid than the preceding, and the interior lustre more brilliant. 



No. 21.— Unio? 

 Can this be the young of Unio No. 18 ? 



I found them frequently in small pools of water, left in the hollows of 

 sand-banks on the Ganges ; they are easily traced by the tortuous fur. 

 r ows which they leave on the sand. They are very slight, and the inte- 

 rior appears to be satiny. 



No. 22. — Cyclas. 

 Epidermis olive-brown, and in some, of different shades of olive-green. 

 Transversely furrowed; beaks sometimes pale purplish, sometimes de„ 

 corticated. 



Found in the Ganges and other rivers. 



No. 23.— Var. 

 Epidermis pale yellow, or dirty straw-colour. 

 In the Ganges at Mirzapoor. 



No. 24.— Var. 

 Some specimens brownish, others pale yellowish, with longitudinal 

 rays or stripes of brown. 



At Mirzapoor in the Ganges, 



