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and seemingly painful struggles. When the skin is completely cast 

 the grub has none of the black spots which before distinguished it, the 

 warts and black hairs are present but the warts are colourless : the 

 head is clear as glass, and the two black eyes so conspicuous in the 

 egg and nevvly hatched grub, are again visible. In about twenty mi- 

 nutes the black spots begin to define, and in about four hours become 

 as distinct and the head as black as before the moult. When the grub 

 has regained its colour it again begins to eat, and eats away night and 

 day without stopping, for four or five days more. It then sickens again 

 for its last moult, and this is performed in the same way as the first : 

 but this time the spots, warts and bristles are cast with the skin, and 

 return no more. The grub is now of a pale delicate green colour, ex- 

 cept the yellow patch near each end, which it still retains. It has now 

 done with eating : when hard enough and strong enough after this last 

 moult, it marches to the stem of the bush, and quietly descends till it 

 reaches the earth : sometimes it crawls along a hanging branch and 

 drops from the extremity. 



The object of gaining the earth is to burrow beneath its surface ; 

 and as soon as the grub once feels the soil, he begins forcing his way 

 into it head foremost, after the fashion of a mole. When he is deep 

 enough to answer his purpose, the depth varying by the way from two 

 to eight inches, according to the hardness or lightness of the soil, he 

 makes a little oblong cell in the earth, and therein spins or constructs 

 a tough black cocoon, attached all round to the walls of the cell : al- 

 though I say spins, the material he uses is not silk or thread, but some- 

 thing between silk and glue, or what we might suppose to arise from 

 the hardening of fluid silk, an illustration rather of the uncouthest, but 

 for want of a better it must go. In this cocoon or case he disposes 

 himself to await the change to a chrysalis, and soon after to a fly. 



The time occupied in this round of existence is very variable : ma- 

 ny of the eggs laid in May, before the middle of the month, produce 

 grubs that go through every change and are again on the wing by the 

 24th of June ; and eggs laid about that day will go through their chan- 

 ges as far as the cocoon by the 10th of July, or loth at the latest: the 

 first brood thus taking about twenty-eight days, and the second gene- 

 rally remaining under ground till the next spring. It is not however 

 clear that in all instances this insect has two broods : on the contrary 

 I am nearly certain that many of the late hatches never reproduce dur- 

 ing the year, but the time of their first appearance is so variable, that 

 a constant succession is kept up, the earliest having reproduced before 

 the later hatches arc gone down. 



