124 



NOCTULE, OR GREAT BAT. 



it will be noticed that, as soon as the swallows retire to rest at dusk, after clearing the air 

 of the diurnal insects,, the bats issue from their homes, and take up the work, perform- 

 ing the same task with the insects of night, as the birds with those of day. Then, as 

 the dawn breaks, out come the swallows again, and so they fulfil their alternate duties. 



NOCTULE, OR ORE AT B\T.NoctuliaiaaltivoIans. 



The NOCTULE is not so pleasant a companion as the Long-eared Bat, for it gives forth 

 a most unpleasant odor. Its cry is sharp and piercing, thereby producing another 

 analogy with the swifts, which are popularly known by the name of " Jacky-screamers." 

 The voice of all British bats is singularly acute, and can be tolerably imitated by the 

 squeaking sound which is produced by scraping two keys against each other. There 

 are many people whose ears are not sensible to the shrill cry of these animals which, 

 in some cases, is rather fortunate for them. I well remember being on Hampstead- 

 heath, one summer's evening, when the air was crowded with bats hawking after flies, 

 and their myriad screams were so oppressive, that I longed for temporary deafness. 

 Yet my companion an accomplished musician was perfectly insensible to the shrill 

 cries, which seemed to pierce into the brain like so many needles. It is also known 

 that many ears are deaf to the stridulous call of the grasshoppers. 



In order to show the sharply-pointed teeth of the insect-feeding bats, the skull of the 

 common bat is here given. 



One use of the tail is, evidently, that it should act as a rudder, in order to guide the 

 flight while the creature is on the wing. There is, however, another purpose which it 

 serves, and which would never have been discovered, had not the 

 bat been watched. It seems that the female bat uses its tail, and 

 the membrane which stretches on either side from the tail to the 

 hind legs, as a cradle, in which to deposit its young when newly born 

 and comparatively helpless. 



Bats are generally found to assemble in great numbers wherever 

 they find a convenient resting-place, and in such localities as church 

 towers, rocky caverns, hollow trees, and the like, they may be found by the hundred 

 together. These numerous assemblies are the cause of a large deposition of guano, 

 which consists almost wholly of the refuse of insects, such as wings, legs, and the harder 

 coverings. In this guano are found, by the aid of the microscope, very many curious 

 infusorial objects, which maybe separated from the guano by the usual modes of prep- 

 aration. 



The odor which arises from this substance is peculiarly sharp and pungent, and can- 

 not easily be mistaken. The animals themselves are readily alarmed when disturbed 

 in their home, they disengage themselves from their perches, and flap about in great 

 dismay, knocking themselves against the intruder's face, much as the great nocturnal 



SKULL OF BAT. 



