PIERIN^. 
185 
spotless greenish-white $ with a scarcely distinguishable as well as 
a pale sulphur-yellow $ with rusty-reddish marginal spots. 
These robust and strongly-made butterflies are very swift on the 
wing, but their rapid and irregular onward flight is constantly inter- 
rupted by settling on flowers. They are also found settled in numerous 
drinking parties on the edges of streams and pools. As mentioned in 
my introductory remarks (vol. i. p. 31), the genus is famous for the 
amazing assemblages of some of its members in onward migration ; 
records of their steadily advancing hosts are numerous from both Old 
and New Worlds, and the solitary African species (which ranges 
throughout the Ethiopian Kegion) is no exception to this remarkable 
tendency. Like Terias, it inhabits all tropical and sub-tropical coun- 
tries, extending also northward as far as Ohio in the United States and 
Syria in the Mediterranean sub-region, and southward to Chili and the 
Cape. 
The food-plants of the caterpillars in both hemispheres are Legumi- 
nosce, and nearly all of those known and recorded are species of Cassia. 
299. (1.) Callidryas Florella, (Fabricius). 
9 Papilio Florella, Fab., Syst. Ent., p. 479, n. 159 (1775); Ent. Syst., 
iii. I, p. 213, n. 666 (1793). 
$ and white Colias Fi/rene, Swains., Zool. Illustr., ist Ser., i. pi. 51 
(1820-21). 
^ and ? $ . Callidryas FJorella, Boisd., Sp. Gen. Lep., i. p. 608, n. 2 (1836). 
5 Callidryas Hyhlcea, Boisd., op. cit, p. 612, n. 7. 
9 Callidryas Rhadia, Boisd., op. cit., p. 617, n. 11. 
^ $ (white). Callidryas Florella, Trim., Rhop. Afr. Aust., i. p. 68, n. 45, 
and Note (1862). 
? Callidryas Rhadia, Trim., op. cit., p. 69, n. 46. 
$ 2 Callidryas Florella, Hopff., Peters' Reise Mossamb., Ins., p. 365 
(1862). 
$ Var. Callidryas Florella, Guen., Maillard, Notes Reunion (Bourbon), 
Lep., pi. 21, ff. I, 2 (1862). 
$ Callidryas Florella, Trim., Trans. Ent. Soc. Lond., 1870, p. 382. 
$ 5 (white). Callidryas Fyrene, Butl., Lep. Exot., p. 44, pi. xvi. ff. 8, 10 
U\ 9 [91 (1870). 
$ Callidryas Florella, Butl., op. at., p. 56, pi. xxii. ff. i, 2. 
$ Var. Catopsilia Aleurona, Butl., Ann. and Mag. Nat. Hist., 4th Ser., 
xviii. p. 489 (1876). 
9 ?Var. Catopsilia rufosparsa, Butl, Ann. and Mag. Nat. Hist., May 
1880, p. 395. 
Callidryas Siuainsonii, Westw., App. Gates' Matabeleland, p. 335 (1881). 
Pupa {West- African), Butl., op. cit., pi. xxii. f. 2a. 
Exp. ah, 2 in. 3-9 lin. ; (^) 2 in. 2-9L lin. 
$ Greenish-white. Fore-wing : a small narrow terminal disco- 
cellular spot, variable in development (especially in length), but usually 
well defined, and very rarely sub-obsolete ; an exceedingly narrow 
faint reddish-brown edging on costa from beyond middle to apex, and 
thence (broken into ill-defined nervular spots) along hind-margin as 
