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are attached. Probably we have given them more power than 

 they possess, and we think it will be found they cannot see so far. 

 Their capacity for keen vision is vastly increased by the almost 

 incalculable number of lenses, with which the eye is supplied ; and 

 those so convex that objects invisible, unless through a microscope 

 that magnifies a hundred andfijty thousand, is clear to them. With 

 one that magnified four hundred and ninety thousand, we counted 

 the lenses with sufficient accuracy, and after repeated trials, came 

 to the conclusion, that there were ten thousand two hundred, not 

 many more or less. This mechanism gives the power of seeing in 

 all possible directions, and we will presently perceive how important 

 it is to the economy of the insect. 



We have already alluded to the peculiar mechanism of the in- 

 struments by which the locust imbibes its aliment, so different from 

 those of the cicada?. They are exceedingly minute, and on a su- 

 perficial view, unappropriated ; but with a fine glass, their office is 

 designated at once. 



They seek nourishment that is always present and ready, pre- 

 pared for the instruments through which they are to receive it. 

 The exhalation from vegetable barks forms their entire subsistence. 

 This they probably could not find without exquisitely keen vision, 

 as they have no olfactory nerves, that can be demonstrated. 

 We are, nevertheless, not to infer positively that they can neither 

 hear nor smell. We must search for another apparatus to find 

 the conduit of their nutriment. The antennae, we have re- 

 marked, are bristle shaped, standing between the eyes and the 

 rostrum or beak which furnishes the avenue through which the 

 nourishment is conveyed. It is in this sense only that the locust 

 can be said to have a mouth. There are three exquisitely fine hairs 

 appended to its extreme points, by which, through a high magnify- 

 ing power, we see them distinctly feeding on the dewy exhalation 

 of vegetable barks a material that may be compared to the in- 

 sensible perspiration of the animal body ; the insensible perspiration 

 of the vegetable skin. Although we cannot demonstrate that they 

 are tubular, they probably act by capillary attraction. The exquisite 

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