226 AMERICAN JOUKNAly 



shoals. Trypanostoma, in still water, near the banks, and lo 

 only where the water is very rapid. Eurycoelon is scarce here, 

 and affects sheltered crevices among the rocks, eschewing mud 

 entirely." 



Supplementary List of Species quoted from printed records 

 as "found in the Holston," not yet received from Miss Law as 

 being found in that stream : 



Unio amoenus, Lea; U. arc/enteus, Lea; * U. compressissi- 

 mus, Lea; U. C'ope/, Lea ; I7.'fassinans,Jjea,; U. mcestus, Lea; 

 U. perjncfus. Lea ; U. jnlaris, Lea ; U. piiniceus, Hald. ; f 3/a?'- 

 garitana Jlolstonia, ,Jje-A; \ G-oniohasis simplex, Say ; % Gionio- 

 basis, glabra, Lea ; G-on. strigosa. Lea ( Try. strigosum, Tryon) ; 

 lo jiuvialis, Say ; lo inermis, Anth. ; Trypanostoma Roanense, 

 Lea ; Trypanostoyna suhro stratum, Lea. 



Species quoted from printed records as found at Knoxville, 

 not yet received from Miss Law as being found in the Holston : 



G-oniohasis Steivardsoniana, Lea ; 1| Gon. Estahrookii, Lea ; 

 Trypanostoma Knoxvilliana, Lea ; Try. prasinatum. Con. ; 

 \ Try. subulceforme, Lea. 



At Chota Shoals Miss Law found specimens of a variety of Aii- 

 culosa, which Mr. Lea refers to '■^ tintinnabuhun." The shells have 

 nearly the form of that species, but are remarkable for a beauti- 

 ful greenish mottled appearance, unlike that of any other shells 

 I have seen from any portions of the Tennessee system of drain- 

 age. They also have a remarkably thin and tender epidermis, 

 which is readily removed in cleaning by treatment that does not 

 similarly affect other shells of the Holston. Until more infor- 

 mation can be obtained respecting them, it is scarcely proper to 

 present them with the expectation that they will be received as a 

 new species. 



3Iohaivk, N. Y., Oct. 24, 1870. 



* The habits of U. compi'essissimus, as stated by Mr. Lea in describing 

 this species, may have kept it from Miss Law's observation. 



t Marg. Holstonia, Lea, occurs in small streams in Monroe and possi- 

 bly also n\ Blount Co. 



X Shells that I have regarded as Gon. Saffordii, Lea, very like Mr. 

 Tryon's figures of G. simplex, occur in Turkey Creek, near Concord. 



§ Gon. glabra occurs in small streams in Monroe Co. ? 



II The ferruginous coating mentioned by Mr. Lea in his remarks on this 

 species is common to shells from creeks in East Tennessee. 



T[ Try. subulwforme, Lea, occurs in Turkey Creek, near Concord. 



