COLIAS IV. 
dently from hybernating larvae. That hybernation takes place in larval stage in 
some districts is unquestionable. Mr. Boll writes me, 8th April, 1878: “When 
I caught the first specimen of Ariadne , in February of this year, in Archer 
County, Texas, on the same day I found a full grown caterpillar and a chrysalis, 
under stones, both which produced Ariadne .” 
The account Mr. Boll gives in his Leipzig paper is in substance as follows: 
The species begins its flight, in Texas, in November, and throughout the winter 
it is to be seen fresh from chrysalis, in warm days. It is common in March, 
rarer in May, and totally disappears in June. The larva feeds on Trifolium 
stoloniferum, running Buffalo Clover, which attains its greatest luxuriance and 
blossoms in April and May, and dies off before the appearance of the last June 
butterflies. It does not spring up again till the advent of the October rains. 
As before stated, the butterflies appear in November, and during the rest of the 
season larvae and butterflies are taken at the same time. It is the opinion 
of Mr. Boll that the eggs laid in June do not develop, owing to lack of food, 
till the summer is past. (I apprehend that if there is any retardation it must 
be with the larvae.) There are four annual broods of this species and the first, 
or winter brood, appearing from November to end of February, is Ariadne. The 
prevailing form in March is Keewaydin, an example of Ariadne being then 
rarely seen. From April to June the form is what Mr. Boll in this paper calls 
Eurytheme, but his April and May examples of the series sent me are what Mr. 
Bean calls the intermediate form, an intergrade leading to Eurytheme. 
Mr. Boll says : “ If we compare the specimens we find a steady increase in 
intensity of color from April to June; the orange-red becomes more fiery and 
extends in the male over the whole upper surface of secondaries, leaving yellow 
only the costal margin of' primaries, while the black marginal band becomes 
broader and broader. Through the influence of the sun the whole orange upper 
side becomes iridescent, with a violet hue, as in the European species, C. Myr- 
midone. This is particularly noticeable during life, and is very brilliant, but grad¬ 
ually fades in dried specimens. The whole under side changes from greenish- 
yellow to deep yellow.’* This is the typical Eurytheme. Mr. Boll adds: “The 
effect of temperature is in perfect harmony with the steady increase in size and 
intensity of color.” This is the result of field observation, and though breeding 
from the egg might show that the members of the series were not quite so 
sharply defined in all cases, it is clear that there is a regular succession of forms, 
and that there is no such intermixture as appears to the northward. The but¬ 
terflies of the fourth, or late summer brood, and which are typical Eurytheme, 
do not hybernate. The length of the warm season admits of the laying of eggs 
by this brood, after which the butterflies die, as do all butterflies shortly after 
