420 MEAX9I0F DEFENCE OF INSECTS. 



think had at that time been the electric centipede {Geopliihts eleclricus.y 

 Lesser having once touched the anal horn of the caterpillar of some 

 sphinx, suddenly turning its head round it vomited upon his hand a quan- 

 tity of green viscous and very fetid fluid, which, though he washed it fre- 

 quently with soap and fumed it with sulphur, infected it for two days.^ 

 Lister relates that he saw a spider, when upon being provoked it attempted 

 to bite, emit several times small drops of very clear fluid.*^ 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 pro- 

 duced, till the spider appeared quite exhausted.^ The caterpillars also of 

 a particular tribe of saw-flies, remarkable for the beautiful pennated 

 antennae of the males (Pteronus)*, when disturbed, eject a drop of fluid 

 from their mouth. Those of one species inhabiting the fir-tree (Pf, 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 hun- 

 dred, 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 twist lifts the anterior part 

 of its body, and emits from its mouth a drop of clear resin, perfectly simi- 

 lar both in odour and consistence to that of the fir.^ What is still more 

 remarkable, no sooner does a single individual of the group give itself this 

 motion, than all the rest, as if they were moved by a spring, instantaneously 

 do the same.® Thus these animals fire a volley, as it were, at tlieir annoy- 

 ers, the scent of which is probably sufficient to discomfit any ichneumons, 

 flies, or predaceous beetles that may be desirous of attacking them. 



Amongst those which annoy their enemies b}' the emission of fluids from 

 their anus are the larger Carabi. These, if roughly handled, will spirt to 

 a considerable distance an acrid, caustic, stinking liquor, which, if it 

 touch the eyes or the lips, occasions considerable pain.^ — The rose- 

 scented Capricorn (^Ceramhyx moschatus) produced a similar effect upon 

 Mr. Sheppard by similar means. The fluid in this had a powerful odour 

 of musk. — The acid of ants has long been celebrated, and is one of their 

 most powerful means of defence. When the species that have no sting 

 make a wound with their jaws, they insinuate into it some of this acid, the 

 eflfluvia produced by which are so subtile and penetrating, that it is impos- 

 sible to hold your head near the nest of the hill-ant {Formica riifa), when 

 the ants are much disturbed, without being almost suffocated. This odour 

 thus proceeding from myriads of ants is powerful enough, it is said, to kill 



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



2 De 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. 



* J urine, Hijmenopt. t. vi. f. 8. 



^ De Geer, ii. 971. 



^ 1 owe the knowledge of this circumstance to Mr. MacLeay. 



^ De Geer, iv. 86. Geofl'r. i. 141. 



