280 Dr. Frederick A. Dixey on the 
present genus, as B. gidica, the ground colour remains 
pale ; but the precostal streak is the only member of its 
series present. In others again, as B. coronea, the black 
spots of S exist in a state of enlargement and fusion, 
while the orange touches occupy nearly the whole of 
the spaces that are left. The hght spets of series I (see 
p. 269) between S and M, which in B. teutonia are only 
touched with orange, are entirely of that colour in most 
specimens of B. coronea. In B. peristhene the amount 
of lhght ground colour is smaller still, but the orange 
costal streak and orange series I are present as in B. 
coronea. Both of these insects, B. peristhene in especial, 
suggest at once a comparison with certain members of 
-the genus Delias, particularly D.nysa and D. momea. In 
these two species the yellow precostal streak and the 
yellow or orange series I are unmistakably present. In 
D. nysa, as in B. peristhene, these constitute the only 
relief to the general dark colour of the wing; while in 
D. momea § is partially defined by the presence of pale 
touches on its mner aspect in addition to the spots of 
series I along its outer margin. 
While the species named suggest a passage in respect 
of this pattern of the underside of the hindwing between 
Belenois and Delias, there is not wanting evidence of 
the same import in the case of other species in which the 
blackening of the hindwing is a less conspicuous feature. 
On the underside of D. belladonna we cannot fail to 
recognize the counterpart of such a hindwing as that of 
B. teutonia ; the dark and light areas occupy with slight 
modification the same relative positions, and the same 
spaces of pale ground-colour that are in B. teutonia 
touched up with deep yellow, are wholly or partially of 
the like colour in D. belladonna ; among these, of course, 
being the precostal margin. ‘he basal portion of the 
hindwing in such species as D. eucharis and D. hyparete 
shows a more general yellow tinge than in D. belladonna ; 
but in both of these, as in other allied species, the 
deeper-coloured precostal streak is perfectly recognizable. 
In very many species of Delias we meet with a new 
feature, much of the ordinary yellow being displaced by 
a brilliant red; but the former colour still displays a 
tendency to cling to the region of the precostal space, as 
may be seen in D. thisbe ; where, however, the precostal 
yellow hardly reaches further outwards than the pre- 
