MEANING OF SHAPER AND COLOURS OF THE MEMBRACIDJE. 
279 
I can imagine no more interesting study for the tropical American naturalist than 
the attempt to discover the meaning of these remarkable shapes by careful observation 
of the living insects under as many different conditions as possible, and especially 
during the periods of prolonged rest and entire quiescence. It is during these latter 
times rather than in periods of activity (including the frequently repeated brief 
intervening pauses) that the true meaning of a cryptic appearance and instinct is to 
be sought. Thus insects which are about by day should be watched going to rest, 
and then observed from time to time during the hours of darkness ; conversely, 
nocturnal forms should be tracked and then watched by day. Insects which require 
the hottest sunshine should be studied in exceptionally cold cloudy weather, &c. 
In thus looking out for the times of complete repose, when a cryptic appearance 
is of the highest importance, Mr. Nelson Annandale’s observations in Malacca 
(1899-1900) should be remembered. He informs me that insect-eating animals retire 
to rest during the hottest hours of the day, and that at this very time insects, 
including such cryptic forms as the stick-like Phasmids, move about freely, assume 
positions and occupy environments in which they are quite conspicuous. Any 
observer who neglects to take account of this aspect of the question can only commit 
himself to random criticism like that which has been often urged against the inter¬ 
pretation of the wonderfully cryptic underside of butterflies of the genus Kallima. 
Because these insects have been seen in conspicuous positions and attitudes during 
the short pauses between successive flights it has been argued that the dead-leaf- 
like underside cannot be for concealment. Let any such observer watch a Kallima 
to rest at the close of a day’s active flight, and his notes and criticism on the subject 
will have value. As it is we are only confronted by the aimless objection that an 
adaptation developed for one purpose is not made use of for another, and with this 
conclusion the movements and attitudes of our English Vanessida, with their cryptic 
undersides, had long ago familiarised us. 
We now reach the second sub-family of Mr. Buckton’s classification, the Hoplopho- 
rince. The cryptic resemblance to thorns in the genus Umbonia (Plates XVI. and XVII.) 
is well known, but here, too, exact observation of the living insects is much wanted. 
The manner in which the red stripes are developed on the green or greenish thorn¬ 
like pronotum is very realistic and convincing. The fact that the females are far 
more completely thorn-like than the males (compare Figs. 1, 2, 3 with 4 and 5 on 
Plate XVI .) may be merely another example of the general principle that the latter sex, 
when it differs from the former, is more cryptic or more completely mimetic, as the 
case may be. The greater needs of one sex have been met by increased perfection in 
those adaptations which are the chief means of defence. 
The remaining genera of the Hoplojohorince, figured by Mr. Buekton, viz., Triquetra, 
