> 
Mimetic Patterns to the Original Form. (al 
on the other hand, points out that in the Pierine group 
before us the habits of the two sexes are different; that 
whereas the females haunt the forest glades in company 
with the Heliconii, the males congregate and fly m the 
open with other species of white butterflies, among whom 
a reddish or brownish insect would be especially con- 
spicuous, and would be very liable to experimental 
tasting.* This fact would seem to supply an active check 
on the development of the pattern in the male, but it 
still leaves undetermined the meaning of so much of 
the Heliconine colouring as does exist, and of this 
Mr. Wallace has offered no explanation. 
I am myself inclined to think that however much it 
may be to the advantage of these male forms to be taken 
under some circumstances for white butterflies of the 
ordinary kind, yet there must be times and occasions— 
probably while the insect is at rest and settled—when 
the partial mimicry of the underside comes into play, and 
tends to afford protection. An instance in support of 
this view exists in Hesperocharis hirlanda (Fig. 12). 
This insect, like the males of those that have just been 
considered, is on the upper surface an ordinary white 
butterfly of the usual kind; the lower surface, however, 
presents an incipient mimetic pattern of a like degree of 
development with those of Mylothris lorena g and 
M. pyrrha 6. This can be no feeble reflection of a 
mimetic pattern complete in the female, for the sexes of 
H. hirlanda hardly differ; moreover H. hirlanda, with 
one or two other forms probably not specifically distinct 
from it, is the only species of its genus which shows any 
approach towards a mimetic coloration. The mimicry, 
slight as it is, must therefore, it would seem, be of some 
service, as otherwise it would in this case be meaning- 
less; and if this be so with H. hirlanda, it is reasonable 
to suppose that whatever amount of protection such an 
approach to the Heliconine pattern confers, is also shared 
by the males of Mylothris. 
A further point of interest that arises in connection 
with H. hirlanda is this—that a mimetic effect which 
generally resembles that of M. pyrrha &, is here reached 
by different means. Hesperocharis, like Mylothris, starts 
no doubt from a regular Pierine form, such as that 
* “Tropical Nature,” 1878, p. 205. 
