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growth, and that the grub or pupa form is not assumed till a short 

 time before they are found at the surface of the earth. While the 

 insect is under ground, gradually acquiring its growth, it performs 

 the functions of digestion and excrementition, we find it furnished 

 with a strait intestinal tube, the upper part of which is expanded 

 into a wider receptacle, and seems to answer for a stomach. When 

 the pupa leaves the ground and the body is almost matured, these 

 organs seem to be almost obliterated, as we find only a wasted 

 membrane that can perform no function, a mere remnant of former 

 vitality. As little or no growth is required after the pupa state, 

 there is no necessity for a stomach, and during the fleeting existence 

 of the insect in open air, no excrementitious matter can be found. 

 The cavity occupied by the digestive organs is now filled by the 

 seminal fluid in the male and the eggs in the female. 



The time between the discovery of the pupa, and its final exit 

 from the earth, is spent in maturing its skin, and acquiring strength 

 to fit it for more active operations, to fulfil its destination. 



During the warmer hours of the day, it is seen peeping from its 

 cell, seeming to enjoy the warm, fresh air. At twilight, or if the 

 temperature fall during the day, they retire to their chambers. In 

 this imperfect state, their progress is slow, and they are unfit to 

 inhabit the open air for eight or ten days. They then cast off their 

 slough, which finishes the short-lived chrysalis state, and become 

 perfect locusts in twenty four hours, and sometime sooner their 

 progress depending, in some degree, on the temperature of the at- 

 mosphere. 



If we descend to the bottom of their chambers, we find them (as 

 already remarked) six, eight, and sometimes ten or twelve inches 

 deep; but as it is generally supposed that their residence is more 

 profound, it is necessary to shew that this is an error, during their 

 pupa state at least. To determine this question, and some others 

 no better settled, we selected for our field of observation, an 

 ancient oak grove of several acres. The upper stratum is a stiff 

 loam, mixed with some gravel, and inclining, in places, to sand At 

 a depth of from two to three feet there is a stratum of pale blue 



