404 
PLINY* S NATUEAL HISTORY, 
[Book XXIX. 
controversy on the subject, seeing that, taken internally, they 
are a poison, attended with excruciating pains in the bladder. 
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 recommending a potion prepared from cantharides, 
the patient was killed in consequence. There is no doubt, 
however, that applied externally they are useful, in combina- 
tion with juice ofTaminian^^ grapes, and the suet of a sheep 
or she-goat. As to the part of the body in which the poison 
of the insect is situate, authors are by no means agreed. Some 
fancy that it exists in the feet and head, while others, again, 
deny it ; indeed the only point that has been well ascertained is, 
that the wings^^ are the only antidote to their venom, wherever 
it may be situate. 
Cantharides are produced from a small grub, found more 
particularly in the spongy excrescences which grow on the 
stem of the dog-rose,^* and still more abundantly upon the 
ash. Other kinds, again, are found upon the white rose, but 
they are by no means so efficacious. The most active of all 
in their properties, are those which are spotted with yellow 
streaks running transversely across the wings, and are plump 
and well-filled. Those which are small, broad, and hairy, 
are not so powerful in their operation, and the least useful of all 
are those which are thin and shrivelled, and present one uniform 
colour. They are put in a small earthen pot, not coated with 
pitch, and stopped at the mouth with a linen cloth, a layer of 
full-blown roses being placed upon them ; they are then sus- 
pended over vinegar boiled with salt, until the steam has pene- 
trated the cloth and stifled them, after which they are put by 
for use. They have a caustic effect upon the skin, and cover 
the ulcerations with a crust ; a property which belongs also 
to the pine- caterpillar^^ found upon the pitch- tree, and to the 
buprestis,^^ both of which are prepared in a similar manner. 
All these insects are extremely efficacious for the cure of 
^1 See B. xxvi. c. 2. gee B. xxiii. c. 14. 
It has been ascertained by experiment that the vesicatory principle 
resides in the wings more particularly. Ajasson remarks, that it is possible 
that the ancients may not have known the genuine Cantharides, the Canth. 
vesicatoria of modern medicine. 
See B. xxiv. c. 74. 
" pityocampae." See B. xxiii. ce, 30, 40, and B. xxviii. c. 33. 
s« See B. xxviii. cc. 21, 33, 42, and B, xxx. c. 10. 
