48 Animal Life 
Another abnormal type of coloration is presented by the White Bats of Central and 
South America. In the common Diclidurws albus the hai of the body is dark- 
coloured for the greater part of its length, but the tips are yellowish or creamy-white, 
as are also the wing-membranes. The first example of this species known to science 
was taken in Brazil while resting in the leaf of a cocoanut palm; and this suggests 
that the peculiar colouring of these bats (one of which is shown in a hanging posture 
on the right side of the coloured plate) is to harmonise with the silvery under-side 
of the leaves of cocoanut palms. 
In all the foregoimg imstances of abnormal coloration im bats, the colours are 
those of the hair and skin. One remarkable species, the African False Vampire 
(Megaderma rons), shown flying on the left side of the lower part of the plate, 
is, however, in at least one portion of its range, in the habit of dyemg its hai, © 
and thus producing a brilliant orange tint in place of the natural brown. ‘This 
hair-dyeing process is brought about by means of a gland on the rump—very similar 
in position to the oil-gland of a bird—by which is secreted a sticky orange- 
coloured powder. Apparently, as I am informed by an observer in the Sudan by 
whom this remarkable fact was first made known, the powder is ejected immediately 
before the bat takes to flight, and from its glutinous nature sticks to the wings and 
the hair of the lower part of the back; the latter being dyed more or less permanently 
yellow. When on the wing in the daytime, this bat, like the Indian plantain bat, is 
said to resemble a huge butterfly or moth. 
This large bat has a very extensive distribution in tropical Africa, ranging from the 
coast of Guinea to Zanzibar, Abyssinia, and the eastern Sudan. In 1878 the late Dr. 
Dobson stated that the only information then available with regard to its habits was 
contained in a note by the explorer Speke. According to this, these bats were met with 
in considerable numbers at Meninga, where they rose singly from the ground, to alight 
sometimes in bushes, but on other occasions again in the grass. ‘This appears to 
indicate,” adds Dr. Dobson, “that Megaderma jfrons hunts for its prey by day as well 
as by night; and the large size of the eyes in this as well as in the other species 
of the genus leads us to consider this very probable. Mr. Blyth has shown that 
M. lyra {the Indian representative of the genus] feeds on grasshoppers and small bats 
(and probably on other small animals); and the individuals of M. frons observed by 
Captain Speke may have been engaged in hunting for grasshoppers and small mammals 
among the long grass.” 
Can it be that some of the creatures on which this bat preys mistake it for a 
butterfly, and thus make no effort to hide themselves when it appears in sight? 
In conclusion, I may state that one of the objects of this article is to draw 
attention to some of the many interestmg problems connected with the habits of 
animals and the adaptation of particular species to their environment that still await 
solution at the hands of naturalists. Without in any way underrating the importance 
of describing species (although I may think that in some instances these are nowadays 
somewhat unnecessarily multiplied), it cannot be too strongly inculcated that the observation 
of the life-history of animals in the field should form an essential part of the duty 
of every collector. Without such knowledge the dried skins are, in a sense, almost as 
valueless as a field-gun without the breech-block. 
