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pale-winged form, appears as a rare aberration in New- 

 York and Ontario, but actually as a spring-emerging one- 

 brooded species in West Virginia — just exactly as if it were 

 an Anthocharis in fact ! From this I think we get a clue as 

 to the origin of Anthocharis — it did not arise from a one- 

 brooded arctic form like P. bryonice, but was rather a branch 

 from a stem which was probably even then double-brooded — 

 and that accounts for its pallor and delicacy of structure, as 

 fits an insect of the temperate zone. 



Orange-tips. — Those species of ^w^'/z^^c/^^r/j' which I regard 

 as coming nearest to the primitive type of the genus ^ do not 

 present orange tips, but since these orange patches are so 

 characteristic of many species it will hardly do to overlook 

 them. In the first place they are developed in the males — 

 which seems to show that they are of the nature of secondary 

 sexual characters, and have perhaps been perpetuated as 

 such from what was once a very rare variety or aberration. 

 Secondly, it is well to remember that both Pieris rapce and 

 P. venosa have yellow aberrations, and even possibly (as I 

 have argued in Entomologist, 1888, p. 112), came from yellow 

 ancestors — and thirdly, in one species at least oi Anthocharis 

 {A. cardamines) there is an aberration (ab. aureojlavescens, see 

 Entomologist, 1888, p. 189), in which yellow takes the place 

 of orange. 



Preparatory stages. — Dr. T. A. Chapman has an excellent 

 paper {Ent. Mo. Mag,, 1888, p. 257), in which he compares 

 the Q^^ of A. cardamines with that oi Pieris rapce — pointing 

 out that the Qg^ of the former becomes orange, while that of 

 the latter is never darker than a pale yellow — and further, 

 that the eggs of cardamines are laid on the flower-heads. 

 Having the eggs of no other Pieris at hand, he goes no 

 further with his comparison, and it might be supposed that 

 these differences were in some sense generic. But it is not 

 so : Pieris protodice is very common in Custer Co., Colorado, 

 and it lays its eggs profusely on Arabis, Sisymbrium and 

 other cruciferous plants. These eggs are orange, and are 

 nearly always laid on the flower-heads oi Arabis, though also 

 frequently on the stem and leaves of Sisymbrium. 



Anthocharis ausonides (var. color adensis, H. Edw.) flies here 

 ^ See also Darwin's Descent of Man, 2nd Ed., p. 312. 



