op the SLUG WORM. 9 



finding many cells whole, fuppofed the larvae within them 

 had perifhed; but on opening fome of them, I found 

 they were alive, and in the fame ftate as on their firft en- 

 trance. I examined both parcels of earth again on the 

 6th of May : the larvae had then juft entered the pupa 

 ftate in both. It appears hence that if all the Slugs of 

 the laft hatch of 1797 had been deftroyed on the trees, 

 there would have remained in the earth a fufficient num- 

 ber to have continued the fpecies. 



On the 21ft of May they began to rife and depofite 

 their eggs. About the 5th of June the young Slugs be- 

 gan to ffiew themfelves, and continued to do fo in great 

 numbers* till towards the end of the month ; and it ap- 

 peared, that the flies not only rofe earlier; but that they 

 continued to rife and depofite their eggs longer this year 

 than in the two former years. 



In the beginning of July the larvae began to defcend; 

 about the 23d, the flies from thefe began to rife, and by 

 the 7th of Auguft the Slugs of the fecond hatch began to 

 appear on thofe trees which had any green leaves remain- 

 ing, in fuch abundance that by the 15th there were from 

 twenty to thirty on a fingle leaf. In the mean time the 

 trees which had been dripped, had thrown out new leaves, 

 at the ends of thofe branches that had not perifhed, from 

 buds, which fhould not have unfolded, according to the 

 ufual courfe of vegetation, till the next fpring; thus anti- 

 cipating the growth of one year, and cutting off the prof- 

 peel: of fruit. 



As the flies continue to depofite their eggs about three 

 weeks, and the period of hatching is as long, the Slugs 

 ape confequently of different fizes : the larger difappear 

 leaving the fmalieft on the leaves. Hence, fome perfons 

 have fuppofed there were three or four hatches in a 

 year; but there are certainly only two. 



Heavy fhowers are faid to deftroy them, and it ispof- 

 fible that a few may be wafhed off; rain appears to be 

 difagreeable to them, and, in fhowers, I have obferved 

 that they make a fafe retreat to the under fide of the 

 leaves, 



Than 



