NYMPIIALINAK: THE GENUS ARGYNNIS. 549 



brown or <iTeenif<li with a l)roa(ler or narrower siibmargiiial yellowish hand, 

 l)or(lere(l hy a suhniarginal and an extra-mesial series of" large silvery or 

 l)nrt" spots ; there are also intra-niesial and prebasal series of similar 

 spots, tiie latter nsiially smaller than the former. 



Life history. These InitterHies are all single brooded, first ai)pearing in 

 Xew England late in June or early in July, continuing to emerge from 

 the chrysalis uninterrui)tedly throughout July and a ))art of August, and 

 not laying their eggs until the last of August or the first of Septeml)er : 

 the eggs thus lie for a long period wholly undeveloped in the ovaries of 

 the female or at least of those which first emerge. So far as I can dis- 

 cover, the period of all European or American species is the same*, with the 

 single exception of A. calippc, of our Pacific coast, which according to 

 Mr. Wright flies only in spring for six Aveeks (Edwards, Butt. N. Am. 

 iii). But in the southern part of the range of our New England species, 

 and probably also in A. Edwardsii, to judge by Mr. Mead's observations 

 in Colorado, there is an interrupted series of emergences from the chry- 

 salis, giving the appearance of two broods. To quote Mr. Edwards : — 



"There are one or two points in the life history of tlie larger Argyunides that are 

 not yct«lear. With us [W. Va.], cybele $ is on the wing from tlie 25th of May to 

 the 10th of June, as I have noticed for several successive years. Probably aphrodite 

 nearly as soon, and [Semnopsyche] diana first appears about the 20th of .June. 

 Shortly after the 1st of June the $ of cybele is to be seen and both sexes abound in 

 the clover fields. By the end of June cybele has become scarce, and the individuals 

 to be seen have lost their freshness and are brolven and worn. It is certain that these 

 early appearing females have not matured eggs and laid them, because at no time 

 from June to August Avill anything Imt rudimentary eggs be found by dissecting, and 

 the eggs do not become distinguishable to the eye until August. They then mature 

 rapidly, and in a few days attain full size. I am confident that no eggs are laid till 

 .\ugust. But about the first of that month and all along to near the end of it there 

 appear in great numbers both fresh males and females, as if just from chrysalis, 

 with no abrasion of the hairs on thorax between the wings, Avhich spot is the first to 

 show Avear. I doubt if an Argynnis could fly two days without thus giving evidence of 

 it. There are flying at the same time many Avorn individuals, especially females. 

 These last are tlie first to deposit their eggs, but shortly after, and up to the time of 

 frosts, the others also are in condition to do the same. I see no [other] explanation of 

 the appearance of these freshly emerged butterflies than that they have formed part of 

 the brood of caterpillars hatched the previous fall, some of which brood yielded tlie 

 butterflies that came out in May and June, and the remainder continued in tlie larval 

 or chrysalis state until August, and upon these last the perpetuation of the species 

 largely depends, for nine-tenths of the June flight must have been destroyed long 

 before August. If I am right, the preparatory stages of the August cybele must con- 

 sume eleven months out of the tAvelve." (Can. eut., vi : 124-5.) 



Xo such interrupted series of emergences has been detected in the 

 history of our three species in Xew England ; but if, as is probable, this 

 is a first step toward true digoneutism, it might well be looked for in 

 southern X^ew England, and should especially be sought for in A. cybele. 

 How this is brought about or what is the cause of the long continued 



*Buciiler, however, records eggs of A. paphia in England, laid as early as .July 30. 



