46 



TK^AM'S OF AN OLD FARM. 



"You understand, of course," I replied, ''that this 

 hard and apparently lifeless object (Fig. 15) which we 

 call a pupa did nothing to inclose itself. The larva 

 'got' itself 'in,' and then be- 

 came a pupa. A few days be- 

 fore it had been seized by a 

 strange restlessness ; it wandered 

 about uneasily ; it refused to eat. 

 What vision of its coming change 

 had iS^ature given the worm ? I 

 believe human beings also are 

 sometimes impressed in some 

 such way before great crises. I 

 have myself experienced, on the 

 approach of such occasions, those 

 indefinable, restless sensations 

 which the moth larva seems to 

 exhibit. Its first step toward 

 forming a cocoon, after a site had 

 been chosen, was to wrap the stem, as you see here, 

 and lash it to the twig above. Then, sinking to this 

 point, it gradually drew around it the adjacent leaves, 

 making a tin\^ arbor or ci'll, which you observe is the 

 framework of the cocoon. "Within this it began to spin, 

 drawing its silken threads from point to point as it 

 moved around the cell. Layer succeeded layer, each 

 overlapping its predecessor, until the grub was quite 

 shut in, and. iMially, this silken case was completed. It 

 then ceased work, and, yielding to the strange drowsy 

 spell which Nature casts upon its kind, it fell into this 



FIG. 1.5. — PUPA OF 

 POLYPHEMUS. 



