508 PSYCHOLOGICAL PHYSIOLOGY. 



Colymbetes, in the hot sulphur baths of Albano, and which died when, 

 placed in cold water. He himself found a specimen of Lyctus Ju^landis 

 Fab., in the warm dung of a hotbed, and cast it into hot water to kill 

 it ; after it had been some time there it was removed, and appeared 

 dead, but speedily again moved, and entirely recovered. Reaumur and 

 De Geer also relate instances of the larvae of the gnats being found 

 frozen in ice, and which revived when the ice melted. One of my 

 acquaintances saw a Dytictts latissimus enclosed in ice, he took it out, 

 and found it alive ; and Alex. v. Humboldt found insects upon the 

 Cordilleras above the limits of snow, which, although not natives of this 

 altitude, yet retained their vivacity at this temperature. 



289. 



The active means of defence which we find in insects are more 

 numerous and more striking to the eyes. Some appear merely defen- 

 sive, in as far as insects which use them can only protect themselves by 

 attitude and appearance : among them we class the sudden torpidity 

 aped by many insects in a moment of danger. Thus the minute Aga- 

 thidia roll themselves up, and appear dead ; thus the Byrrhi and 

 Anobia contract their limbs, and pretend death so long as they are in 

 the hands of their enemies. Others stretch out their limbs, as Gco- 

 irupcs slercorarius, and thus imitate dead insects. Among the Hy- 

 menoptera the ruby-tails (Chrysodea) adopt the first plan of deceiving 

 their enemies, by rolling themselves up when caught, and only arouse 

 themselves upon the departure of their enemy. Others, particularly 

 the tortoise beetles and Curculios, endeavour to secure themselves upon 

 the approach of an enemy by suddenly falling down from the leaves 

 upon which they were seated, that they may thus conceal themselves 

 among the leaves and blades of grass ; if they are found here they si- 

 mulate death, but not with the obstinacy of the species of the preceding 

 genera. Those active means of defence which may likewise be used as 

 defensive weapons are very numerous, and partly consist in large man- 

 dibles and other pinching instruments, and partly in concealed stings. 

 All the carnivorous beetles are furnished with the iirst kind of arms, 

 namely, the Carabi, Cicindelce, Dytici, Staphylinl, &c. In general, 

 however, the bite of these creatures is not injurious, and with the 

 exception of the pain occasioned by the mechanical injury, the bite has 

 no prejudicial consequences. Among the vegetable feeders also there 

 are many, as the Dynastcs, Lucanus Cervus, many Capricorn beetles, 



