schaeffer: donaciini of the new world. 51 
abundance of the different species differs very much. In the same 
locaHty and on the same plants may be found generally from three to 
five or even more different species but they are never found all at the 
same time. On one small pond in South Jersey, Mr. Wenzel took eleven 
different species in one season. 
The earliest recorded date of occurrence of Donacias on plants is 
the middle of March in Alabama, where Mr. Loding takes vicina on 
Sparganium. Further north in New York and New Jersey parvidens 
and caerulea are the earliest species and appear before others in May, 
the latter species on the leaves of the yellow water lily and the former on 
the leaves of the white water lily. 
Several species have been found very late in fall, early and late 
winter and very early in spring by sifting. These and possibly others 
undoubtedly hibernate. 
Three species in the material loaned to me have caused a little 
trouble before I thought of comparing them with the European spe- 
cies. Two are in Mr. Leng's collection. One of these is an old worn 
specimen of semicuprea labelled "Ct.," the other a specimen of impressa 
labelled "Torrington, Ct., R. Hochstein." The third species was in the 
British Museum material sent me by Mr. Arrow and proved to be 
discolor labelled "Am. bor." As no other specimens of these species 
have been found in North America there is scarcely a doubt that they 
were wrongly labelled. D. dentata was once recorded as occurring in 
North America but has been dropped from our Hst by Mr. Leng in his 
revision. However, Prof. Jacobson in 1892 records it again as occurring 
in North America, but there are no American specimens of this European 
species in any of our collections and I am sure that it does not occur here. 
In concluding the preliminary remarks there remains yet the pleasant 
duty of acknowledging the assistance received in the loan and gift of 
material and other favors. 
Mr. Gilbert J. Arrow of the British Museum of Natural History 
in London, England, and later Mr. Bryant have kindly aided in comparing 
specimens with the types of Kirby, Newman and Lacordaire and Mr. 
Arrow also sent me their unnamed North American Donacias and 
Mexican specimens of Haemonia nigricornis and Donacia cincticornis. 
Mr. Julius Weise of Warmbrunn, Germany, sent me a number of 
European species, which helped greatly in the correct determination of 
certain American species described by Lacordaire, which the latter, in 
his remarks, had compared with some European species. 
Prof. A. Jacobson of Leningrad, Russia, forwarded a number of 
