SEASONAL POLYMORPHISM. 



125 



Palaearctica, p. 132, pi. xxx., fig. 9 (Jan., 1908), in a greater or lesser 

 number of individaals, chiefly of the third generation. This takes 

 place in particularly arid localities of the extreme south (I have found 

 it, however, as far north as Piedmont, where I collected it on a barren 

 hill above Ponzone, m. 600, near Acqui), and then only in certain 

 regions. In Italy, for instance, well characterised specimens are 

 scarce and only transitions are to be met with, as a rule, even in 

 apparently most suitable localities, so that I know none in which one 

 could extend the name to the entire race, as can be done to series from 

 the Bosphorus, whence came my " type," or from Andalusia (Sierra di 

 Alfacar). The features of nitida consist in its small size, short and 

 broad wings, absence of gray basal suffusion, and sharply defined 

 outline of black markings, which are also of a very deep tone. It 

 evidently is a grade of variation towards the North African and 

 Corsican albulice, Obth., which is another grade along the same line of 

 variation, leading up to the extreme race aethiopx, de Joannis and 

 Verity, BM. Soc. Ent. Ital., xliv., p. 120, fig. 2 (1913), of Abyssinia, 

 figured also in Rliop. Pal., I.e., fig. 7 ; the latter, however, deviates 

 from that line by its large size in some cases, and by its limited, but 

 sharply defined, underside green pattern, which does not tend to turn 

 pale yellow and disappear, as in alhidice (see pi. xxx., fig. 29, of Ilkop. 

 Pal.). Race aetkioim points remarkably to P. (ilauconome, Klug. The 

 characteristics of the small first brood of daplidice, described and 

 named helUdice by Ochsenheimer a century ago, are so well known (see 

 pi. XXX., figs. 17 to 25 of Wioj). Pal.), that I need waste no words on 

 it. What I must point out here, because, curiously enough, as in the 

 case of the other Pieridi, no writer seems to have perceived it, is the 

 difference between the second and the third brood. In the former 

 the average size is considerably larger (13 to 41 mm. of expanse, as 

 compared to an average of 39 to 40, and a maximum of 40 in male 

 and of 43 in female of third brood), and giants of over 45 mm. are not 

 unfrequent. The black markings of upperside are often pale and 

 dusted with gray, thus recalling hellidice, in this respect, in extreme 

 examples; this faintness of the pattern is particularly striking in 

 some females. On the underside the tinge of the green tends to be 

 lighter and more yellow, so that females in which that colour is 

 replaced by yellow (form riavopicta, Vrty., Ilhnp. Pal., p. 166, pi. xxx., 

 fig. 11 (June, 1908), are found more often. Talking of this character 

 I might mention that, in daplidice in general of the summer broods, 

 the female is on an average considerably yellower than the male. I 

 have given the name of ed-pan^a to the second generation in the Ent. 

 Rec. of May, 1919, but at that time I thought even within the 

 boundaries of Tuscany, whence I described it from Florence, the large 

 form was only produced locally ; instead, I since have clearly seen that 

 it is constant in all the European localities, from which specimens 

 have been sent, in Italy, Switzerland, France, Spain, and Southern 

 Russia. A slight difference is to be noticed in the number and size of 

 the giant individuals ; dwarfs are found everywhere, but strike one as 

 aberrations, not being connected to the average size by a decreasing 

 series of intermediate forms (ab. nana, Vrty., Ehop. Pal., p. 166) ; in 

 my series of " types " of eqiansa, from Mt. Fanna, m. 600, near 

 Florence, there is one with tbe features of nitida. As to the third 

 generation, I think it should bear the name of daplidice, except in the 



