MUSSELS OF CUMBERLAND RIVER AND TRIBUTARIES. 51 



Nearly all we found were dead shells, iisuallj^ badly eroded at the umbones. Mr. 

 Boepple found the species as far down as Cloyds Landing and in the Obey Eiver at 

 Celina. As found, the epidermis is generally jet black, usually due to the shells 

 being stained. On being cleaned with acids they exhibit beautiful rays. This is a 

 small species of no commercial importance. 



24. Lampsilis parva (Barnes). 



Rare; none at all in the Cumberland; indeed it has not been reported from that 

 river. But we obtained one specimen in the East Fork of Stones River at Water- 

 ville. This was a slender shell; length 27 mm., height 15 mm., width 11 mm. Nacre 

 beautifully white and iridescent. 



25. Lampsilis glans (Lea). 



Rare; none at all in the Cumberland; 10 specimens from the tributaries. Those 

 found were in gravel in shallow and rather swift water. In general it prefers quiet 

 streams with muddy banks and burrows in the firm mud. It is also frequently found 

 in lakes. 



One of the smallest of our species; too small for commercial use, and with a rich 

 puqjle nacre. In one specimen, a female found in Roaring River, the peculiar 

 glands of the mantle, small white cylindrical objects on each side, were protruded 

 and were undergoing spasmodic movements. 



26. Lampsilis alata (Say). Pancake; pink hatchet-back. 



Wliile not a rare species in the Cumberland, this is not especially common. In a 

 few of the beds it is entirely absent, and in many only one or two shells were found. 

 It never exceeded 4 per cent of the catch of any of the beds, and is usually loss than one. 

 It is well distributed tliroughout the entire river. It prefers rather deep water and 

 a soft, muddy bottom. The shell, on account of its thinness and red nacre, is of no 

 value whatever. 



27. Lampsilis gracilis (Barnes). Paper-shell. 



Frequent enough to be a rather familiar species among clammers, but not so abun- 

 dant as to be a nuisance. It has much the same distribution as alata, but is less common. 

 We usually obtained only 1 or 2 from a bed. Our shells are rather badly worn at the 

 umbones. As this thin-shelled species is of no value whatever, but readily catches 

 the mussel hooks, it proves to be a nuisance when present in large numbers where 

 clamming operations are being carried on. 



28. Lampsilis Isevissima (Lea). Paper-shell. 



Rare; only one specimen found in the Cumberland; this was at Meeks Spring Bar. 

 It seemed to be more common in the Harpeth. This species closely resembles L. 

 gracilis in general appearance, but has, among other distinguishing features, a beauti- 

 fully polished epidermis. Our examples have a number of peculiar rays, consisting 

 not of a different pigmentation of the epidermis but of a series of short, finely wrinkled 

 lines. 



29. Lampsilis leptodon Rafinesque. 



This fragile, thin-shelled species is rare in the Cumberland. The only examples 

 obtained were collected by Mr. Boepple at Albany and Cloyds Landing in the autumn 

 of 1910. 



30. Medionidus conradiciis (Lea). 



This species is confined chiefly to small streams. It is exceedingly abundant in 

 the Rock Castle River at Livingston, Ky., the sandy bottom being almost covered 

 with these animals, which showed up as narrow black lines, the mantle and exhalent 

 and inhaient apertures being thin and black. It is also abundant in Roaring River. 



In the Cumberland we found it just below the falls and at Salt Lick Island. All 

 the shells were badly stained and eroded, and for this reason, as well as on account 

 of its small size, it has no commercial value. 



