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temporary dwelling, is analogous to the habits of other animals, 

 especially the hybirnating, such as alligators, tortoises, frogs and 

 others which immerse themselves beneath their natural element 

 into a uniform temperature, merely high enough to be susceptible 

 of excitement by the vernal return of heat. Although the locust 

 does not lie torpid, instinct directs it to provide for its own preser- 

 vation by insuring a steady temperature that answers all the pur- 

 poses of its economy. 



Is not the migration of birds regulated by the same principle? 

 They instinctively seek more congenial climes to evade the seda- 

 tive influence of cold. 



A more minute account of those apartments will shew how well 

 they are adapted to the purposes of self-preservation, and how 

 much better they are directed by instinct than they could have been 

 by any contrivance human reason could invent. 



On a first view of the external opening of the chambers we 

 would suppose that they run in a perpendicular direction; but we 

 find them deviating more or less: some running horizontally, others 

 at obtuse or acute angles, while some form entire circles. All 

 these varieties, and their modifications, are found where there is no 

 impediment to a perpendicular ascent, which they meet some- 

 times. They come up occasionally under the roots of trees, floors, 

 logs, stones and pavements laid since their descent. In such cases 

 they pursue any course by which they can reach the surface; but 

 they sometimes fail from the distance they have to travel. We 

 found many that had perished under a brick pavement that had 

 been laid over them after their descent. 



The roofs of their tenements are neatly arched, and so firmly 

 cemented that water is never found in them, though all th6 sur- 

 rounding grounds are overflowed and perfectly saturated. This 

 defence against an element that would be destructive, is to be at- 

 tributed to the workmanship of the cells, the interior of which are 

 varnished with a secretion that seals them hermetically, from bot- 

 tom to top, and makes them water proof. The locust is not singu- 

 lar in this provision against inundation and drowning. The cray- 



