62 CANTHARIDiE — BLISTER-FLIES. 



1709, and arrived at its height in 1783, when the number of 

 trees destroyed by it in the above-mentioned forests alone 

 was calculated at a million and a half, and the whole num- 

 ber of insects at work at once one hundred and twenty 

 thousand millions. The inhabitants were threatened with 

 a total suspension of the working of their mines, for want 

 of fuel. At this period these Bostrichi, when arrived at 

 their perfect state, migrated in swarms like bees into Suabia 

 and Franconia. At length a succession of cold and moist 

 seasons, between the years 1784 and 1789, very sensibly 

 diminished the numbers of this scourge. In 1790 it again 

 appeared, however, and so late as 1796 there was great rea- 

 son to fear for the few fir-trees that were left.^ 



Cantharidae — Blister-flies. 



Many species of this family of insect possess strong vesi- 

 cating powers, and are employed externally in medicine to 

 produce blisters, and internally as a powerful stimulant. 

 Taken internally, Pliny considered them a poison, and 

 mentions the following instance of their causing death : 

 Cossinus, a Roman of the Equestrian order, well known 

 for his intimate friendship with the Emperor Nero, being 

 attacked with lichen, that prince sent to Egypt for a 

 physician to cure him ; who recommended a potion pre- 

 pared from Cantharides, and the patient was killed in con- 

 sequence.^ But there is no doubt, however, Pliny adds, 



1 Wilhelm's Recr.from Nat. Hist., quot. by Latrielle, Hist. Nat,, ix. 

 194. Quot. by Kii-b. and Sp. Introd., i. 213. Carpenter, Zool., ii. 133. 



2 Brookes informs us that Dr. Greenfield, a practitioner in Lon- 

 don, was sent to Newgate, by the college, for having given Can- 

 tharides inwardly. This happened in the year 1698 ; but he was 

 soon after released, by a superior authority, when he published a 

 work upon the good ett'ects of these insects taken inwardly for 

 strangury, and other disorders of the kidneys and bladder. We 

 are also told by Ambrose Parry, that a courtezan, having invited a 

 young man to supper, had seasoned some of the dishes with the 

 powder of Cantharides, Avhich the very next day produced such an 

 effect, that he died with an evacuation of blood, which the physi- 

 cians were not able to stop. Many other instances might be 

 brought, continues Brookes, of persons that have been either 



