Vescicating Insects 55 



While blister beetles have been especially used for external applica- 

 tion, they are also at times used internally as a stimulant and a 

 diuretic. The powder or extract was formerly much in vogue as an 

 aphrodisiac, and formed the essential constituent of various philters, 

 or "love powders". It is now known that its effects on the reproduc- 

 tive organs appear primarily after the kidneys have been affected to 

 such an extent as to endanger life, and that many cases of fatal poison 

 have been due to its ignorant use. 



There are many cases on record of poisoning and death due to 

 internal use, and in some instances from merely external application. 

 There are not rarely cases of poisoning of cattle from feeding on 

 herbage bearing a large number of the beetles and authentic cases are 

 known of human beings who have been poisoned by eating the flesh 

 of such cattle. Robert states that the beetles are not poisonous to 

 birds but that the flesh of birds which have fed on them is poisonous 

 to man, and that if the flesh of chickens or frogs which have fed on 

 the cantharidin be fed to cats it causes in them the same symptoms 

 as does the cantharidin. 



Treatment of cases of cantharidin poison is a matter for a skilled 

 physician. Until he can be obtained, emetics should be administered 

 and these should be followed by white of egg in water. Oils should 

 be avoided, as they hasten the absorption of the poison. 



Other Cryptotoxic Insects Though the blister beetles are the 

 best known of the insects with poisonous blood plasma, various 

 others have been reported and we, shall refer to a few of the best 

 authenticated. 



One of the most famous is the Chrysomelid beetle, Diamphidia 

 simplex, the body fluids of whose larvae are used by certain South 

 African bushmen as an arrow poison. Its action is due to the presence 

 of a toxalbumin which exerts a haemolytic action on the blood, and 

 produces inflammation of the subcutaneous connective tissue and 

 mucous membranes. Death results from general paralysis. Krause 

 (1907) has surmised that the active principle may be a bacterial toxine 

 arising from decomposition of the tissues of the larva, but he presents 

 no support of this view and it is opposed by all the available evidence. 



In China, a bug, Heuchis sangmnea, belonging to the family 

 Cicadidae, is used like the Meloidas, to produce blistering, and often 

 causes poisoning. It has been assumed that its vescicating properties 

 are due to cantharidin, but the presence of this substance has not. 

 been demonstrated. 



