Page:Popular Science Monthly Volume 9.djvu/560

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THE POPULAR SCIENCE MONTHLY.

special function are mainly two: First, the form of the teeth; and, secondly, that of the stomach.

As to the teeth, the grinding ones are reduced to a minimum both as to size and number; while the two middle or cutting teeth of the upper jaw are of great size, with a sharp cutting edge well fitted to inflict the small incision needful for the animal's nourishment.

As to the stomach, it presents us with a structure unique in the animal kingdom. Here it is not the pyloric end of the stomach, but the opposite or cardiac end, which is produced into an enormously long pouch, while the opposite or pyloric end is reduced to a mere rudiment—the highly-nutritious food (blood) requiring very little digestion, but needing a capacious chamber for its speedy reception.

Although this is the only bat perfectly organized to live by bloodsucking exclusively, nevertheless it is probable that various other kinds practise blood-sucking as at least one part of their mode of nutrition.

The late distinguished zoölogist belonging to the Zoölogical Society, Mr. Blyth, has observed this habit in a leaf-nosed bat of India, one belonging to quite another family than that to which the American vampire belongs. The bat in question is called Megaderma Lyra. Respecting its habits Mr. Blyth tells us[1] as follows:

"Chancing one evening to see a rather large hat enter an out-house from which there was no other egress than by the doorway, I was fortunate in being able to procure a light, and thus proceed to the capture of the animal. Upon finding itself pursued, it took three or four turns round the apartment, when down dropped what at the moment I supposed to be its young, and which I deposited in my handkerchief. After a somewhat tedious chase, I then secured the object of my pursuit, which proved to be a fine pregnant female of Megaderma Lyra.

"I then looked at the other bat which I had picked up, and, to my surprise, found it to be a small Vespertilio, nearly allied to the European V. pipistrellus, which is exceedingly abundant, not only here, but apparently throughout India, being the same also, to all appearance, as a small species which my friend Dr. Cantor procured in Chusan. The individual now referred to was feeble from loss of blood, which it was evident the Megaderma had been sucking from a large and still bleeding wound under and behind the ear; and the very obviously suctorial form of the mouth of the vampire was of itself sufficient to hint the strong probability of such being the case. During the very short time that elapsed before I entered the out-house, it did not appear that the depredator had once alighted: but I am satisfied that it sucked the vital current from its victim as it flew, having probably seized it on the wing, and that it was seeking a quiet nook where it might devour the body at leisure. I kept both animals wrapped separately in my handkerchief till the next morning, when, procuring a convenient cage, I first put in the Megaderma, and, after observing it some time, I placed the other bat with it. No sooner was the latter perceived than the other fastened on it with the ferocity of a tiger, again seizing it behind the ear, and
  1. In the "Journal of the Asiatic Society of Calcutta," vol. xi., p. 225, quoted in P. Z. S., 1872, p. 713.