94 



Nevada and Colorado are usually immaculate and not distin- 

 guishable from Olcracca hyemalis. This form and typical Venosa 

 are considerably unlike, but their summer generations approach 

 and are often precisely alike. The summer generation of 

 Venosa is Pallida Scudder, described ; ^ as •' immaculate, yellowish 

 beneath, with sometime a few indistinct grayish scales scattered 

 along the nervules ; otherwise quite immaculate. The female 

 has, in addition, a band of grayish scales on the posterior border of 

 primaries, and a spot or cluster of grayish scales in upper median 

 interspace." All this is but the description of many examples of 

 Oleracea mstiva $ , and of all males. But the variety of the 

 summer form of Venosa, which has a black spot on primaries, was 

 not before Mr. Scudder when he drew up his description. This 

 is Castoria, Reakirt, the male only described ; it is said to have 

 ^^ a rounded black spot on the medio-superior interspace of primaries ; 

 no other markings; underneath immaculate." Castoria, then, is 

 one sub-form. Pallida the other, and both undoubtedly appear in 

 same brood, i. e., in the generation following and proceeding from 

 Venosa, 



Of four $ under view from Lake Lahache, Brit. Col., 2 are 

 immaculate {Pallida), 2 have a light spot {Castoria). I have but 

 one ? and that has no spot, but the marginal border is gray. 

 From Vancouver's Island i ^ is immaculate, one has half a dozen 

 scales only in place of a spot ; but a third $ has a black spot. 

 With these are 2 2 and both have the two spots of N'api and 

 dark border. i $ from Oregon is immaculate. Four males 

 from Washington Terr, are immaculate ; but the 2 ? with them 

 have both spots and the border. 0)ie of these is yelloiv on upper 

 side. Two males from California have the upper spot only, their 

 females both spots and the border. One female from southern 

 Colorado has both spots and border, but the males accompanying 

 are immaculate, and may be called either Pallida or Oleracea 

 (Estiva. 



It appears therefore that while several males from the Pacific 

 coast, under view, are immaculate {Pallida), about one-half have 

 the spots in greater or less degree {Castoria), but that all the 

 females except one have, on the upper surface, the spots and 

 dark border to primaries which characterises Napi, and the one 

 exception has the dark border. One female Pallida from Wash- 

 ington Terr, is of a pale but decided yellow on both surfaces — 

 another departure. I have noticed this in no Oleracea cestiva. 

 Just as from Rajycp., in New England, there has developed a yellow 

 form, the Nova-Angliae of Scudder. 



We have seen then that starting with the common form 

 Bryonice, the next generation, Napim Europe, Venosa in America, 

 differs perceptibly. Also that Venosa has an offshoot in Oleracea 

 hyemalis which occupies a more extensive territory than the 

 parent. Now the second generation of these two, which corre- 



