Proceedings of the South African Philosophical Society. xXxxv 
resemblance of its under surface to a faded leaf, sits, according to: 
Trimen, on the stems and among the branches of trees, where, 
the wings being folded, it becomes invisible. Precis archesia,. 
P. natalica, P. elgiva are models of assimilation. The colouration 
of these species is not that of withered leaves, and any one who. 
remembers the pattern and colour of their under side is not sur- 
prised to learn that the first species delights to repose on rocks and 
large stones, and that the second often settles on the ground, because 
of the similarity of their markings to the colour of the places on 
which each kind rests. 
Frequently described is the fixed resemblance to environment. 
which is found in the Kallima butterfly, in which not only is the 
under side of the wings exactly like a dead or brown leaf with a 
very apparent mid-rib, but the apices of the hind wing are so pro-- 
duced as to resemble the leaf-stalk, while the creature rests or stands 
in such a way that its tail appendices touch a branch, thus better’ 
simulating a stalk. 
The South African Precis tugela affords as good an example of 
protective resemblance. Precis cuamia, another South African 
species, 1s also very leaf-like, but does not quite reach the 
perfection of the other. 
Among the Moths, we find protective resemblance due to coloura-- 
tion still more intensified. This group of butterflies has mostly 
sombre hues, but there are some which have brilliant colours, and 
these examples are mostly diurnal forms. When present, as in 
some of the diurnal Zygende and Agaristide, &c. (Pais decora, 
Aiigocera fervida), they are danger signals, and do not come into the 
category of protective colours. Of course there are exceptions, but: 
brillant colours for protection by harmonising with the surroundings. 
are rare. Among those I doubt if there is a more striking object: 
than the Silver Moth (Leto venus), with its crimson body and fore- 
wings covered with brilliant silvery lamelle, thus resembling the 
Orthopterous Cystocelia guttata and Pnewmora variolosa, which, 
like Leto, are also: nocturnal. 
No one not an entomologist can realise the extraordinary keen- 
ness of scent developed in the male insect for mating purposes. 
The unfortunate female, especially among LEprpopTERA, is often 
mobbed by her suitors. Numbers of examples of many moths are 
caught by the simple device of enclosing a captured female in a. 
small muslin bag. Males will flock to it from all parts of the 
neighbourhood. It would thus be quite unsafe to consider these. 
glittering, silvery patches as beacons of light for the species to 
attract one another. The olfactory power of the male is sufficient. 
