372 



possible that the fly couldbreed in a body poisoned either before or after death with ar- 

 senic, butin " Forensic Medicine and Toxicology," Woodmaii and Tidy, page303,i8 an 

 extract from " Lancet," August 23, 185ii, page 2151, in which the statement is made that 

 " one hundred and fifty pheasants were poisoned from eating the maggots generated 

 in some animals destroyed by a strychnia vermin-killer. " I do not know whether to 

 believe this or not. If we have a fly here in Indiana which can kill a man in mid win- 

 ter and half devour him within two years, poison and all, it will be worth knowing. 

 A physician in the city made the analysis and gave me the flies, and has promised 

 me that if it is necessary to exhume the corpse, I shall have the opportunity to inspect 

 it. If you wish more material, or think of any points which can he cleared up iu 

 regard to the insect, please write me, and if the chance is offered I will get them. 



Please, however, before printing anything on the subject, let me get all the facta 

 possible in the case, when I will put them iu shape and send you. Can you figure 

 the different stages with the material you have?— [ F. M. Webster, La Fayette, Ind., 

 February 12, 1890. 



Reply. — Your letter of the 12th has come to hand, and this further information 

 makes the case of the corpse flies even more interesting. In the first place I do not 

 think there is any possibility that the flies or their larvps killed the man, and the case 

 which you mention from the Lancet is rather improbable. I do not at all doubt that 

 the flies could flourish in the body of the man had he been poisoned by taking a dose 

 of arsenic, but it is less probable that they could live in the body if it had been thor- 

 oughly embalmed by injecting the usual arsenic and corrosive sublimate mixtures. 

 Even the latter, however, is not so improbable as it would at first appear, for many 

 of these Dipterous larvie are very tenacious of life and very little affected by poison. 

 I should by no means say that the fact that they lived in the body and bred in such 

 great numbers is proof positive that the body had not been embalmed. Ptinid larvae 

 have been known to feed in the corks of bottles containing corrosive sublimate. 



I find on examining the specimens here that they were kept in water tooloug to be 

 in good condition for figuring. If you have other better flies send them on, and if 

 you have an opportunity to secure fresh ones, let me have a set placed directly in 

 alcohol, I will, however, have as good a figure as possible made from those which 

 we have here. — [February 15, 1890,] 



The May Beetle and the White Grub. 



Have you given any attention to the period of abundance of the May Beetle, Lach- 

 nosterna fusca, and have you thought it worthy to forecast the year of swarming and 

 attack on their favorite trees for food, as the walnut, hickory, butternut, and ash, 

 invariably stripping off all the June foliage of that year ? You are familiar with the 

 life history, indeed your observations are the only ones made by an American ento- 

 mologist on the common American form of dor-beetle, in reference to its transforma- 

 tions to full development, and I presume you have published the year of great swarm- 

 ing at vai'ious times. 



I have noted for many years their stages of growth and length of larval and imago 

 life, and by taking the three-year period easily predict their years of swarming, which 

 were for the last decade 1883, 1836, 1889, and will come again in 1892. I have fol- 

 lowed this series of broods backward and find it agrees with the swarming iu Ala- 

 bama in 1880, and that in Massachusetts iu 1865; also that recorded in eastern New 

 York in 1850. Certainly there is a small number of beetles on the wing every year, 

 and there must be, therefore, two other series of broods, occupying the two interven- 

 ing years. 



I know that the entomologists of Europe predict the year of abundant swarming 

 for their common dor-beetle (a triennial period also, I believe) which led to much 

 l^reparation for destroying them ; but, uufortuuately for the reputation of those wise 

 bug-men, something about the weather, fungous diseases, or parasites interrupted, 



