THE ALFALFA CATERPILLAR. 17 
July 23. Following this the intestinal disease attacked the larvae 
so generally that Mr. Wilson found it impossible to continue genera- 
tion records. Nevertheless, he states in his field notes that a fourth 
generation was out by the latter part of August. We thus see that 
there are in the colder sections of the country two generations an- 
nually and in the extreme warmer sections at least six and possibly 
more generations each year. 
FOOD PLANTS. 
Alfalfa seems to be the favorite food plant, but there are quite 
a number of others. The two buffalo clovers, Trifolium reflexvm 
and T. stoloniferum, were probably the original native food plants. 
For some years the species was thought not to live upon red clover 
(T. pratense), but Mr. E. H. Gibson, at Greenwood, Miss., and Mr. 
W. H. Lar rimer, at Nashville^ Tenn., proved conclusively that it 
does attack red clover. They collected both eggs and larvss from red 
clover and reared them to adults. During the summer of 1913 the 
writer collected the larvse feeding upon few-flowered Psoralea {Psora- 
lea tenuifiora) at Koehler, N. Mex., and Mr. Larrimer, at Nashville, 
made some interesting experiments, besides those on red clover. 
Using larvae that hatched indoors, he reared them from the following 
plants that had not already been reported as food plants: Alsike 
clover {T. hybridum), soja bean {Glycine hispida), Canadian field 
peas {Pisum sativum), and hairy vetch {Vicia sativa). Repeated 
attempts to rear them on cowpeas {Vigna sinensis) resulted in fail- 
ure. He says : " On hairy vetch they seemed to thrive exceedingly 
well and completed their life history in a shorter period than on any 
other food plant." In July, 1910, the writer found larvae feeding 
on sweet clover {Melilotus alba), which, strangely enough, they 
seemed to prefer to a patch of alfalfa growing close by. Eggs were 
observed to be very numerous upon the leaves of the sweet clover 
at the same time. Besides alfalfa and the buffalo clovers ; Scudder 1 
has recorded Hosackia, ground plum {Astragalus caryacarpus) , and 
A. crotalarice as food plants. The adults visit blooming plants for 
nectar, and they have been reported, doubtless erroneously, as feed- 
ing upon many of these. The butterfly is known to oviposit on 
toothed medicago or bur clover {Medicago hispida). Mr. E. H. 
Gibson, at Greenwood, Miss., reported females ovipositing on coffee 
weed {Sesban macrocarpa), which they curiously preferred to red 
clover growing near by. 
1 Scudder, S. H. The Butterflies of the Eastern United States and Canada, v. 2, Cam- 
bridge, 1889, p. 1132. 
48305°— Bull. 124—14 3 
