Stonb-Hason Caterpillars. 249 



as the first, the texture of the walls being much slighter, 

 while it was more rounded at the apex, and of course not so 

 elegant. Reaumur found, in all his similar experiments, 

 that the new structure equalled the old ; but most of the 

 trials of this kind which we have made correspond with the 

 inferiority which we have here recorded. The process 

 indeed is the same, but it seems to be done with more hurry 

 and less care. It may be, indeed, in some cases, that the 

 supply of silk necessary to unite the bits of stone, earth, or 

 lichen employed, is too scanty for perfecting a second 

 structure. 



We remarked a very singular circumstance in the opera- 

 tions of our little architect, which seems to have escaped 

 the minute and accurate attention of Reaumur. When it 

 commenced its structure, it was indispensable to lay a foun- 

 dation for the walls about to be reared ; but as the tent was 

 to be moveable like the shell of a snail, and not stationary, 

 it would not have answered its end to cement the foundation 

 to the wall. We had foreseen this difficulty, and felt not a 

 little interested in discovering how it would be got over. 

 Accordingly, upon watching its movements with some atten- 

 tion, we were soon gratified to perceive that it used its own 

 body as the primary support of the building. It fixed a 

 thread of silk upon one of its right feet, warped it over to 

 the corresponding left foot, and upon the thread thus 

 stretched between the two feet it glued grains of stone and 

 chips of lichen, till the wall was of the required thickness. 

 Upon this, as a foundation, it continued to work till it had 

 formed a small portion in form of a parallelogram ; and 

 proceeding in a similar way, it was not long in making 

 a ring a very little wider than sufficient to admit its body. 

 It extended this ring in breadth, by working on the inside 

 only, narrowing the diameter by degrees, till it began to 

 take the form of a cone. The apex of this cone was not 

 closed up, but left as an aperture through which to eject its 

 excrements. 



It is worthy of remark, that one of the caterpillars which 

 we deprived of its tent attempted to save itself the' trouble 



