HYBERNATION OF CATERPILLARS. 195 



from particular facts seldom accord with actual na- 

 ture, and ought never to be indulged in by natural- 

 ists who study accuracy. Another caterpillar, not 

 uncommon in gardens, on the hollyhock and other 

 plants, would at once disprove such an inference : we 

 allude to that of the angle-shades {Phlogophora me- 

 ticulcsa, Ochsenheimer). This caterpillar, which is 

 exceedingly smooth, and is remarkable for changing 

 in its last moult from a clear green to yellowish 

 brown, we have found during the whole winter in 

 the folds of the fresh leaves of hollyhocks, cabbage- 

 lettuce, savoys, &c., quite lively, and feeding in open 

 weather by no means sparingly. Its defence from 

 cold may perhaps consist in a superabundant supply 

 of fat, which we may infer that it possesses from the 

 soft flabby aspect. It is this circumstance which 

 seems to protect whales from the polar cold, as well 

 as bears during their torpidity. 



Some caterpillars seem to have no less power of 

 resisting severe cold than eggs ; as authentic in- 

 stances are recorded of their revival after being frozen 

 stiff — a circumstance also reported of some serpents 

 in North America*. Dr. Lister in this way revived 

 caterpillars frozen so hard as to chink like stoneb 

 when thrown into a glassf; and Mr. Stickney ex- 

 posed some grubs of a common crane-fly {Tipula 

 oleracea, Linn.) to a severe frost, till they were con- 

 gealed into masses of ice, yet several of them sur- 

 vived |. Reaumur, however, was unsuccessful in 

 similar experiments on the gregarious moth of the 

 fir {Cnethocampa Pityocampa, Stephens), so cele- 

 brated among the ancients as a poison § ; for none of 

 them survived a cold of 2° below zero, Fahr., by 

 which they were frozen to ice||. 



* John Hunter, Obs. on Anim. Econ. p. 99. 



f Goedart, Insect, p. 79. J Kirby and Spence, Inlr. ii. p. 453. 



§ Piin. HUt. Nat. 38, 9. IJ Mem. ii. 



