Satyrus Sthenele Boisd.
Is rather common near San Francisco, where it is found in June. Only one generation annually.
Satyrus Sylvestris Edwards.
Edwards’ description shows very clearly the marks by which S. Sylvestris can be recognized from S. Sthenele. This species is found on grassy hills thinly covered with live-oak, where its habits show a very marked difference from those of its relations, by preferring the underside of oak branches to any other seat, while Sthenele and Boopis almost exclusively settle on the ground.
Satyrus Boopis Behr.
Sthenele similis at limbus non tesselatus, sed linea transversa distincte partitus et fœminæ ocelli alarum superiorum in fascia dilutiori positi. Alae subtusdimidiatæ pars radicalis brunnea, marginalis grisea, marginem versus brunnescens. Utraque marmorata, halone ocellorum in alis anticis solo excepto dilutiori et concolori.
This Satyrus is the biggest of our Californian species, the male being nearly double the size of the female of S. Sylvestris. I find this Satyrus in July in Contra Costa, on the hills as well as on the plains. In regard to the diagnosis of these three closely allied species, I would mention, that the presence or absence of one or two more or less distinct eye-marks, on the upper or under side near the anal angle of the hind wings, is of no diagnostic importance.
S. Ariane Boisd.
I confess I can not find any constant mark of difference between this species and S. Alope, Nephele, and Pegala, however different at first glance their forms may appear. I am very much inclined to consider them local aberrations of one far spread species, that gradually slopes from S. Pegala Fabr., through S. Ariane Boisd. to S. Nephele and S. Alope Fabr., in a similar way as the Gerontogeic P. Egeria L. looks very different from its African form P. Xiphia Fabr., with which, nevertheless, it is insensibly united by its intermediate form P. Meone.