COLIAS IV. 



dentlj from hybernating larva^. That hybernatiou 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. lioll 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 

 .stolonilerum, running Buffido 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 Octoljcr rains. 

 As before stated, tlie butterflies appear in November, and during the rest of the 

 season larvaj 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 larva\) There are four amuial l)roods of this species and the first, 

 or winter brood, appearing from November to end of February, is Ariadne. The 

 prevailing form in March is Keeivaydin, an example of Ariadne being then 

 rarely seen. From April to June the form is what Mr. Boll in this paper calls 

 Eurythenie, but his April and Ma}' examples of the series sent me are what Mr. 

 Bean callathe intermediate form, an intergrade leading lo 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 prinuiries, while the black marginal band becomes 

 broader and broader. Through the influence of the sun tlie whole orange upper 

 side becomes iridescent. Avith 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 layijig of eggs 

 by this brood, after which the butterflies die, as do all butterflies shortly after 



