408 MEANS OF DEFENCE OF INSECTS. 



stag-horn Capricorn beetle (Prionus Cervicornis) in America, may save them 

 from the cruel fate of the poor cockchafer 1 , whose gyrations and motions, 

 when transfixed by 'a pin, too often form the amusement of ill-disciplined 

 children. The threatening horns also, prominent eves, or black and dis- 

 mal hue of many other Coleoptera belonging to Linne's genera Scarabceus, 

 Cicindela, and Carabus, may produce the same effect. 



But the most striking instances of armour are to be found amongst the 

 homopterous Hemiptera. In some of these, the horns that rise from the 

 thorax are so singular and monstrous, that nothing parallel to them can be 

 found in nature. Of this kind is the Cicada spinosa Stoll 2 , the Centrotus 

 clavatus 3 , and more particularly the Centrotus g/obularis 4 , so remarkable for 

 the extraordinary apparatus of balls and spines, which it appears to carry 

 erect, like a standard, over its head. What is the precise use of all the 

 varieties of armour with which these little creatures are furnished it is not 

 easy to say, but they may probably defend them from the attack of some 

 enemies. 



Under this head I may mention the long hairs, stiff bristles, sharp 

 spines, and hard tubercular prominences with which many caterpillars are 

 clothed, bristled, and studded. That these are means of defence is ren- 

 dered more probable by the fact that, in several instances, the animals so 

 distinguished at their last moult, previous to their assuming the pupa (in 

 which state they are protected by other contrivances), appear with a 

 smooth skin, without any of the tubercles, hairs, or spines for which they 

 were before remarkable. 5 Wonderful are the varieties of this kind which 

 insects exhibit : but I shall only here select a few facts more particularly 

 connected with my present subject. The caterpillar of the great tiger- 

 moth (Euprepia Caja), which is beset with long dense hairs, when rolled 

 up an attitude it usually assumes if alarmed cannot then be taken 

 without great difficulty, slipping repeatedly from the pressure of the 

 fingers. If its hairs do not render it distasteful, this may often be the 

 means of its escape from the birds. That little destructive beetle Anthrenus 

 Musorum, which so annoys the entomologist, if it gets into his cabinets, 

 when in the larva state being covered with bunches of diverging hairs, 

 glides from between your fingers as if it were lubricated with oil. The 

 two tufts of hairs near the tail of this are most curious in their structure, 

 being jointed through their whole length, and terminating in a sharp 

 halberd-shaped point. 6 I have a small lepidopterous caterpillar from 

 Brazil, the upper side of which is thickly beset with strong, sharp, branch- 

 ing spines, which would enter into the finger, and would probably render 

 it a painful morsel to any minor enemy. 



The powers of annoyance by means of their hairs, with which the moth 

 of the fir, and the procession-moth, before noticed, are gifted, are doubtless 



1 One would almost wish that the same superstition prevailed here which 

 Sparrman observes is common in Sweden, with respect to these animals. " Simple 

 people," says he, " believe that their sins will be forgiven if they set a cockchafer 

 on its legs." Voyage, i. 28. 



2 Cigales, f. 85. " 



3 Ibid. f. 115. Coquebert, Illust. Ic. ii. t. xxviii. f. 5. 



* Stoll, Cigales, f. 163. Comp. Pallas, SpiciL Zool. t. i. f. 12. 



5 Reaum. v. 94. 



6 This was first pointed out to me by Mr. Briggs of the post-office, who sent me 

 an accurate drawing of the animal and of one of its hairs. I did not at that time 

 discover that it had been figured by De Geer, iv. t. viii. f. 1. 7. 



