“The wound made by them is very difficult to heal, especially in its usual locality—the tip of the great toe—as it generally renders a shoe unbearable for a day or two, and forces me to the conclusion that, after the first time, for the curiosity of the thing, to be bitten by a Bat is very disagreeable. They will, however, very rarely enter a lighted room, and for this reason the practice of burning a lamp all night is almost universal.”
In the island of Muciana, situated in the mouth of the Amazon River, Mr. Wallace had an opportunity of observing the mischief done by these blood-sucking Bats on a large scale. The island is used as a grazing-ground, but some of the horses and cattle on it, says Mr. Wallace, were “miserable-looking objects, from wounds inflicted by the Bats, which cause them to lose much blood, and sometimes, by successive attacks, kill them. Senhor Leonardo informed us that they particularly abounded in some parts of the island, and that he often has Bat-hunts, when several thousands are killed.” Mr. Wallace describes the criminal in this locality as a large coffee-brown Bat, probably the Phyllostoma, hastatum. He adds that they “live in holes of trees, where they are killed in considerable numbers, Senhor Leonardo informing me that they had destroyed about seven thousand during the last six months. Many hundreds of cattle are said to have been killed by them in a few years.”
Mr. Louis Fraser, when collecting at Gualaguzia, in Ecuador, obtained a specimen of the Javelin Bat, and was told by the Indian who brought it to him that this species attacks the Mules.
Prince Maximilian of Neuwied also lays the crime of blood-sucking at the door of the Javelin Bat. He says:—“In its stomach I found remains of different kinds of insects, but never any traces of blood that had been swallowed; nevertheless, it is certain that this and many other species of Phyllostomes suck the blood of animals. I have never surprised such a Bat at the moment of sucking, but have observed in the moonshine and twilight how these large animals fluttered, with strongly rustling wings, about our grazing beasts of burthen, which bore their vicinity quietly, but on the following morning were covered with blood, from the shoulders down to the hoofs. On the Rio das Contas we found the cattle quite exhausted with the loss of blood.” The same author adds:—“As I have never found blood in the stomachs of the Phyllostomes, this nutriment can only be partaken of by them rarely, and for this reason I do not venture to decide whether some, or all, or what species of them are fond of this food; but with regard to the largest species here described, it needs no further confirmation, and I believe that of all the Phyllostomes described by me, it is nearly the only one that sucks blood.”
MOUTH OF SPECTACLED STENODERM.
It will be seen from the foregoing statements that there is some uncertainty as to the precise species which may justly be charged with the crime of blood-sucking. The habit has been ascribed to various species, some of which are now known to feed upon fruits, whilst others find their nourishment in the abundant insect population of tropical America; and in the opinion of many zoologists of the present day, the sole criminals are the species of the genus Desmodus, a small aberrant group, specially distinguished from all the rest by the structure of their teeth and stomach. Mr. Tomes, in commenting on Mr. Fraser’s statement, suggests that the blood-sucking was performed by the Desmodonts, which accompanied the Javelin Bat in Mr. Fraser’s collection, and the guilt transferred to the larger and more striking species; and the same explanation may apply to the accounts given by Mr. Wallace and Prince Maximilian, both of whom apparently charge the Javelin Bat with sanguinivorous proclivities solely upon circumstantial evidence. If this be the case, Phyllostoma hastatum must be regarded as a very unfortunate animal. Professor Reinhardt agrees with Mr. Tomes in considering the Desmodonts (Desmodus and Diphylla) the only blood-sucking Bats, and they appear to be the only forms that have been actually taken in the fact.
At the same time we are perhaps hardly justified in passing a verdict of not guilty in the case of some of the other species, for certain observers record the finding of blood in the stomach, and by others the structure of the mouth is looked upon as furnishing circumstantial evidence of sanguinary propensities. Thus Professor Bell says that the tongue in the genus Phyllostoma has a number of wart-like elevations, so arranged as to form a complete circular suctorial disc when they are brought into contact at their sides, which is effected by a set of muscular fibres having a tendon attached to each of the warts. By means of this curious sucker, he adds, these Bats are enabled to suck the blood of animals and the juice of succulent fruits. According to other writers the papillæ which are borne by the lips (see [figure]), and which seem to have some analogy with the wrinkles occurring on the lips of the Mastiff Bats, serve this same office; and Prince Maximilian especially describes the mode in which the lips in the Javelin Bat may be converted into a sucking-canal. It is to be observed, however, that these papillae are greatly developed in species which are now known to derive the whole or the greater part of their nourishment from fruits.
BLAINVILLE’S BAT.[234]
