NORTH AMERICAN COLEOPTERA. 
159 
REVISIO]^ OF THE DOXACT.E OF BOREAE AMERIC A. 
BY CHARLES W. LENG, B. S. 
Donacia was established by Fabricius, in 1775, for a European 
species allied to our mbtilis, and the name, derived from the Greek 
donax — a reed, — is indicative of the habits of that and the other 
species comprised ; all are subaquatic, the larvie feeding in, the im- 
agines being found about reeds, pond lilies, Sagittaria and other 
water plants. The earliest descriptions of our species are by foreign 
authors, Ahrens and Kunze, in 1810 and 1818 respectively. Thomas 
Say described five in 1823 and 1827, Newman added others, and 
Kirby still more. In 18-15 there was published a “ Monographie” 
by Lacordaire, which swelled the number considerably. In 1851, 
Dr. LeConte reviewed the described species, noting many synonyms, 
and in 1873 Crotch made a Synopsis, on which the names now in use 
are based. In all, about 70 names have been proposed, and over 
100 pages printed in descriptions. 
Some confusion still existing, I have attempted in the following 
pages to give the characters by which the really distinct species may 
be recognized. Unassisted, this would have been both presumptuous 
and impossible; but in advice and material I have received so much 
help, that I hope the result may be found satisfactory. To Dr. Geo. 
H. Horn I owe the free use of a collection representing all the de- 
scribed species, each one specially compared with the types of Dr. 
LeConte’s s[>ecies in the Cambridge Museum ; as well as the results 
of his observations on the genus for many years back. Through 
the favor of Prof. C. V. Riley, I have been entrusted with the col- 
lection of the National Museum. To Mr. Frederick Blanchard I 
owe many valuable suggestions and sets of the species living on the 
Concord River. To Messrs. Roberts, Liebeck, Westcott, Wickham, 
Hulbert and Sherman, my thanks are due for specimens. Finally, 
my friends on Staten Island, William T. Davis and J. C. Thompson, 
have freely given me the use of their collections and time. 
Before using the synopsis, the reader should observe the following 
explanation of the terms employed. 
“ Elytra truncate at tip, or subtruncate.” Under this head are 
included all the forms that are in the least truncate, or even doubt- 
