202 



MEANS OF DEFENCE OF INSECTS. 



mediately cry out as if hurt : repeating the experiment with 

 another of his boys, he complained of its making him smart : 

 upon this he touched himself with it, and it caused as much 

 pain as if, after shaving, he had rubbed his face with spirits 

 of wine. This he observed was not invariably the case 

 with this beetle, its saliva at other times being harmless. 

 Hence he conjectures that its caustic nature, in the instance 

 here recorded, might arise from its food ; which he had reason 

 to think had at that time been the electric centipede (Geo- 

 philus electricus). Lesser having once touched the anal horn 

 of the caterpillar of some sphinx, suddenly turning its head 

 round it vomited upon his hand a quantity of green viscous 

 and very fetid fluid, which, though he washed it frequently 

 with soap and fumed it with sulphur, infected it for two 

 days. 1 Lister relates that he saw a spider, when upon being 

 provoked it attempted to bite, emit several times small drops 

 of very clear fluid. 2 Mr. Briggs observed a caterpillar caught 

 in the web of one of our largest spiders, by means of a fluid 

 which it sent forth entirely dissolve the great breadth of 

 threads with which the latter endeavoured to envelop it, as 

 fast as produced, till the spider appeared quite exhausted. 3 

 The caterpillars also of a particular tribe of saw-flies, re- 

 markable for the beautiful pennated antenna? of the males 

 (Pteronus) 4 , when disturbed eject a drop of fluid from their 

 mouth. Those of one species inhabiting the fir-tree (PL Pint) 

 are ordinarily stationed on the narrow leaves of that tree — 

 which they devour most voraciously in the manner that we 

 eat radishes — with their head towards the point. Sometimes 

 two are engaged opposite to each other on the same leaf. 

 They collect in groups often of more than a hundred, and 

 keep as close to each other as they can. When a branch is 

 stripped they all move together to another. If one of these 

 caterpillars be touched or disturbed, it immediately with a 



1 Lesser, 1. i. 284. note 6. 



2 JDe Araneis, 27. 



3 This gentleman is of opinion that spiders possess the means of re -dissolving 

 their webs. He observed one, when its net was broken, run up its thread, and 

 gathering a considerable mass of the web into a ball, suddenly dissolve it with 

 fluid. He also observes, that when winding up a powerful prey, a spider can 

 form its threads into a broad sheet. 



4 Jurine, Hymenopt. t. vi. f. 8. 



