MEGACHILE. 277 



perpendicularly to her body. In a direct line she wings 

 her way to the receptacle, and arrived at the mouth of 

 the aperture within which she has to convey it, she rolls 

 it to its requisite tubular form and thrusts it forward to 

 the bottom of the cavity. The first piece for the lining 

 of each cell is always oval and larger in proportion than 

 the succeeding ones, which, to the number of three or 

 four, are semicircular, the first piece having an extra 

 use to serve in forming a concave bottom to the cavity. 

 Having completed the requisite manipulation, for ad- 

 justing it to shape the external lining of the bottom arid 

 sides of the first cell, she withdraws backwards, again 

 flies off, and, as if she had traced a trail in the air, or 

 had marked its limpidity with a frothy surge, like 

 that left in the wake of a ship, to note the road for 

 her return, back she wends to the same plant, and proxi- 

 mately to the spot of her recent triumphant exploit re- 

 news the operation, but the result of which, this time, is 

 to be semicircular. Home she flies again, and the ar- 

 rangement within of this piece is different to that of the 

 first, for this is simply tubular, and so placed that it 

 imbricates with its cut margin within the serrated edge 

 of the first and the third, and in case of a fourth the 

 fourth also is similarly placed, so that one laps within the 

 other, the edges of two of these cuttings never being 

 conterminous. The number of the coatings is apparently 

 regulated by the drier or moister condition of the sub- 

 stance in which the tunnel is drilled. Another duty has 

 now to be performed, indeed, that for which all the pre- 

 ceding labours were undertaken, the provision for its 

 young, wherein it perpetuates its kind, and thus on 

 and on flows the wonderful stream of life, whose origin 

 who shall estimate through the millennia it has hitherto 



