458 SUPPLEMENT 



Aratu ((/rapsus pictusj. It is pounded, and a potion made 

 of it with wine : it acts as an emetic. 



The ancients, in like manner, boast of the anti-poisonous 

 qualities of the Crustacea, and the employment of them may 

 certainly prove salutar}', in circumstances where the use of 

 alkalies is required. M. Arthaud has caused death to 

 chickens, by causing them to be stung by the large crab- 

 spider of the Cape of Good Hope fmygale cancerides, Lat.). 

 This species, according to him, frequents humid places, kills 

 and sucks large insects, kakerlaks, and often its own con- 

 geners. He maintains that this mygale often perishes, by 

 the sting of a sort of gadfly under the belly, most probably in 

 the organs of respiration. The touching of this last arane'ide, 

 or rather its hairs, produce severe smartings, similar to those 

 caused by the introduction of the hairs of certain caterpillars, 

 into the epidermis. 



Though sound criticism may authorize us to call in doubt, 

 or suspect of exaggeration or partiality, the testimony of some 

 travellers, or of some historians respecting the venomous 

 powers of these araneides, prudence, enlightened by observa- 

 tion, forbids us to deny the existence of their poison, or to 

 lull ourselves in a fancied security against the dangers which 

 it may occasion. Here, as in so many other cases of uncer- 

 tainty, further experiments will be necessary to decide our 

 judgment. 



The hairs of these mygales, as we have already hinted, 

 make the same impression upon the skin as the hairs of cer- 

 tain caterpillars. " One morning, as I was getting up, one 

 of the Spanish travellers made an exclamation on seeing on 

 my garments, from the feet even to the shoulders, a brown trace, 

 occasioned by the passage of one of these crab-spiders, and by .- 

 an acrid and caustic liquor which distils continually from 

 its mouth and feet. Happily it passed innoxiously while I 

 was sleepmg profoundly, and contented itself with thus 



