392 General Notes. [June, 
ZOOLOGY: 
Synonymous Unios.—The following synonomy is based upon 
series of shells received from Prof. Witter, Muscatine, Iowa, and 
Dr. J. Schneck, Mt. Carmel, Ill., purporting to be Unio nasutus. 
That both series represented the same species was beyond doubt, 
but that it was U. nasutus was as plainly to be doubted. From 
obvious resemblances they were compared with U. xashvillensis 
Lea, and U. mississippiensis Con., and the several series were found 
to be identical, and it was further established that none of them 
were U. nasutus. The comparison was based upon the position and 
form of the cicatrices, the size, position and angulation of the 
teeth, crenulation of the lateral teeth, color of the nacre and of 
the epidermis (after treatment with oxalic acid to remove ferru- 
ginous matter). Then came the query, “which is which?” The 
western collectors all call the shell U. nasutus, which is evidently 
incorrect. Masutus is a flat, slender shell, and, like U. complan- 
atus, belongs to the Atlantic slope, though ‘both Mr, Lea and Mr. 
Say assert that “ the species inhabits the western waters.” 
r, Lea in his Synopsis of the Unionidae, p. > Er on j 6 
himself points out a possible solution. He SAS 
nasutus inhabits the western waters, a variety oft that boot ae 
ave been described by him (Mr. Say) for subrostratus.’ Here a 
thought suggested itself that both Mr. Lea and Mr. Conrad had 
described a zew species, varieties of Say’s older suérostratus. In 
sh perplexity the — were submitted to my friend Dr. Lewis, - 
Moh r further study and correction. We com- 
pared them. with Say's description of subrostratus, with typical 
series of the other species mentioned above, and they were pro- 
nounced by him to be identical. Subsequent to this, after my ar- 
rival again East, Dr. Lewis writes (May 17, 1878), “I have got to 
the bottom of the synonomy of the shells you had from Dr. 
Schneck. He and many of the western collectors call the shell 
wrongly U. nasutus Say. It is U. subrostratus Say. Add to it the 
synonomy of U. zashvillensis Lea, and of U. mississippiensis Con., 
and you have it all complete.” He further says, “ Mr. Lea makes 
subrostratus a synonomy of iris, Lea followed Say, who was i in 
error as to what was zis, which it is clear he had not seen.’ 
Say’s subrostratus, therefore, stands as a good species, and, 
because of its era of publication (1831), we must write as its 
synonyms U. nashvillensis Lea, and U. mississippiensis 
There is a ery diference $ in the outline of the shell in the 
sexes of all these species. Nor is this difference without marked 
positions of the various organs. Every one, who has dissecte 
any great number of Unios, knows full well the differences in rela- 
1The departments of Ornithology and Mammalogy are conducted by Dr. ELLIOTT 
Coues, U. S. A. 
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