_Lycæna pseudargiolus_ is subject to great variation, and occurs under many forms, most of which having been regarded as distinct species. In the early spring Violacea appears, and is characterized by dimorphism in the female, some of that sex being blue, others black. This form, which may be called the winter form, deposits its eggs in the clusters of flower-buds of the Dogwood, the young larvæ obtaining their first food by boring into the buds, but later on eating their way into the ovaries. The flies that come from these larvæ late in May are Pseudargiolus, which, as stated before, lays its eggs on _Cimicifuga racemosa_, most of the resulting butterflies over-wintering to produce Violacea. A small percentage of the May chrysalids give butterflies as late as September, which are smaller than the parent-form, and also differ therefrom in the more decided character of the marginal crescent discal spots on the under side of the wings. There does not seem to be any regular second summer brood, that is, there are but two regular annual broods, the Violacea of March and the Pseudargiolus of May, the individuals happening to emerge in July, August and September being irregular visitants, for which the name of Neglecta has been given. The females of the last form lay their eggs upon _Actinomeris squarrosa_, and the chrysalids, thence resulting, give Violacea the next spring. Larvæ feeding on Dogwood vary much in color from those that feed on the Black Snakeroot, few being white in the last stages, but nearly all dull-crimson or green, or a mingling of the two. Nevertheless, a small percentage of the larvæ on _Cimicifuga racemosa_ are also green or crimson, though the most of them white. Ants do not seem to visit the larvæ on the Dogwood, and on being introduced to them in confinement treat them with indifference. On rare occasions tubes have been discovered in the eleventh segment, fully expanded, and accompanied by a pulsating movement, but no teasing or irritating availed to make them appear. Even severe pressure applied to the sides of the segment failed to force out any fluid. As with the fall food-plant, _Actinomeris squarrosa_, the Dogwood is neither sweet nor juicy, and it is possible that the larvæ feeding on these plants do not secrete the fluid.