402 Mr. Marsham's Account of 



yard af the arsenal at Toulon. Many years since a row of the 

 Lombardy poplar was planted on the border of a foot path 

 leadino- to the Dog and Duck in St. George's Fields, and soon 

 afterwards two of the B. 9-maculata of Ent. Brit, were taken from 

 the trunks of those trees ; but I have not heard that any more of 

 the same species have been taken in Great Britain. 



Thd destructive property of these insects to timber is now 

 evident: and. the length of time that this animal lay concealed 

 strengthens an opinion which I have, from several causes, long 

 entertained, that, by the dispensation of Providence, nothing 

 once created shall be entirely lost ; but, that although a series 

 of unfavourable seasons may succeed each other, so as to de- 

 stroy the greatest part of many animals, yet a remnant shall 

 remain to propagate and continue the species. In confirmation 

 of this remark I shall mention one instance, which occurred to 

 my friend William Jones, Esq. of Chelsea, and which I do not 

 recollect to have seen published. This gentleman in one of his 

 entomological excursions took a female of the Fhalcena Bombyx 

 mendica, which laida number of eggs that produced thirty-six cater- 

 pillars : all of these fed, spun their cases, and went into the pupa 

 state in a regular manner: but at the proper season only twelve 

 came out in their perfect state; and as this was no uncommon 

 circumstance he concluded that the rest were dead. To his great 

 astonishment however, the next season twelve more made their 

 appearance, and the following year the remainder burst into life, 

 equally perfect with the foregoing. How is this extraordinary^ 

 fact to be accounted for, except by the abovemcntioned supposi- 

 tion ? They all fed alike, spun up about the same time, were 

 equally exposed to the same atmosphere of heat and cold, and 

 yet the result was so widely different. The question I am 



aware 



