( xcvi ) 



these hybrids when they breed together would produce " off- 

 spring of which 50 per cent, must resemble the parents (i. e. 

 are heterozygotes), while 25 per cent, are pure dominants 

 (astyanax) and 25 per cent, are pure recessives (arthemis). 

 Farther north, where astyanax seems not to thrive, but the 

 recessive white-banded arthemis holds sway, occasional stray 

 examples of proserpina, mating with arthemis, will yield 

 offspring of which 50 per cent, will be proserpina and 50 per 

 cent, pure arthemis* In this division the Springfield brood 

 probably belongs. South of the zone of hybridization the 

 white band must be almost swamped ; for when proserpina . 

 mates with astyanax, the offspring will all be dark, and half 

 of them will be pure dominants (astyanax)." The occasional 

 white-banded Basilarchias taken south of the zone the author 

 interpreted as among the 25 per cent, of extracted recessives 

 produced by the occasional " interbreeding of southward- 

 spreading heterozygotes (proserpina) ." It must be remem- 

 bered, however, that these southern extracted recessives are 

 not pure, inasmuch as they resemble " astyanax (ursula) in 

 many ways, yet having the white band well developed on all 

 the wings " (Field, 1904, p. 4). 



The author's third paper in " Psyche " was entitled " Hybrid 

 butterflies of the genus Basilarchia " (vol. xxi, No. 4, 1914, p. 

 115, Plate VII). A pairing was secured and lasted about half 

 an hour, on Aug. 20, 1910, between a bred female archippus and 

 a male of arthemis captured at Alstead Center, New Hampshire. 

 The female in seven days laid 62 eggs on and near the leaves 

 of willow. Only 19 larvae hatched — none of them " from 

 eggs laid toward the end of the period of oviposition." Eight 

 imagos emerged, all males and all like the 3 captured speci- 

 mens of arthechippus figured in the first paper. A ninth pupa 

 which did not emerge was, from its small size, considered 

 to be a male. Efforts to mate these males with females of 

 arthemis, archippus, astyanax and proserpina led to no results, 

 although marked sexual excitement was evident in both males 

 and females. Two of these male arthechippus were represented 

 on Plate VII. 



* The Mendelian interpretation of Edwards' 1877 results was also 

 suggested in Trans. Ent. Soc. Lond., 1908, p. 473. 



