APRIL, 1914. MAMMALS OF NORTHERN PERU OSGOOD 179 



region we traversed. In the jalcas at elevations of 10,000 feet or more, 

 we had no evidences of them, but at altitudes between 1,000 ft. and 9,000 

 ft. they are generally distributed. Certain localities are noted for them 

 and are avoided by mule drivers as much as possible. At Hacienda 

 Llagueda and near Cajamarca, we found them roosting in caves, and 

 old mine shafts or prospect holes. In such places, the ground beneath 

 the suspended bats is usually filthy with accumulated excrement. It 

 sometimes forms great pools of dark brown digested blood more or less 

 watery or viscous in the center and gradually hardened or encrusted at 

 the edges. A very large cave which we examined near Molinopampa 

 must have contained several thousand of these bats and some of the 

 pools of excrement were two to three feet deep. 



Our pack mules were constantly subject to attack from bats and the 

 steady annoyance and loss of blood affected their general condition 

 very rapidly. The point of attack was almost invariably at the top of 

 the withers, apparently because this is one of the parts the victim is 

 least able to protect. The wound inflicted shows on examination how 

 effective is the highly developed cutting machine. A small nearly 

 round button of skin about one fourth of an inch in diameter is removed 

 and after the bat has sucked its fill, blood continues to flow for some 

 time, streaking down the animal's sides and even to its forelegs. Just 

 how far an animal might be persecuted is uncertain but it seems quite 

 possible that one weakened or temporarily defenceless might be put to 

 death by its bloodthirsty tormentors. One of our mules was bitten 

 thirteen times in a single night and it was not uncommon for one or 

 more of them to show eight or ten wounds when it was brought in from 

 a night at large. It was noticed that some of the mules were bitten 

 much less frequently than others; in fact, one animal which was easily 

 the most sagacious and always in better condition than the others was 

 practically exempt throughout the trip. That this was due to superior 

 ability to ward off the pests was quite apparent, especially since toward 

 the end of the trip the animals in poorest condition continually suffered 

 more and more than those not so weakened physicallv from other 

 causes. 



On two occasions our men were bitten by bats, once when we were 

 sleeping in the same room with them in a house in Moyobamba, the 

 men in an alcove at one end and ourselves in the main room with doors 

 open for free ventilation. I heard bats flying about during the night 

 but supposed they were the common Hemiderma until morning when 

 one of the men came out with a sheepish look on his face and held up his 

 bare foot showing one of the characteristic round punctures on the end 



