520 INSTliNCT OF INSECTS. 



lieii which should lay her eggs in a hot-bed, and cease 

 to sit upon them. 



The adaptation of means to an end not likely to 

 have been provided for by instinct, is equally obvious 

 in the ingenious mode by which a nest of humble-bees 

 propped up their tottering comb, the particulars of 

 which having before mentioned to you% I need not 

 Iiere repeat. 



There is perhaps no surer criterion of reason than^ 

 after having tried one mode of accomplishing a pur- 

 pose, adopting another more likely to succeed. Insects 

 are able to stand this test. A bee which Huber watched 

 while soldering the angles of a cell with propolis, de- 

 tached a thread of this material with which she entered 

 the cell. Instinct would have taught her to separate 

 it of the exact length required ; but after applying it 

 to the angle of the cell, she found it too long, and cut 

 off a portion so as to fit it to her purpose ''. 



This is a very simple instance ; but one such fact is 

 as decisive in proof of reason as a thousand more com- 

 plex, and of such there is no lack. Dr. Darwin (whose 

 authority in the present case depending" not on hearsay, 

 but his own observation, may be here taken,) informs 

 us, that walking one day in his garden he perceived 

 a wasp upon the gravel walk with a large fly nearly as 

 big as itself which it had caught. Kneeling down he 

 distinctly saw it cut off the head and abdomen, and then 

 taking up with its feet the trunk or middle portion of 

 the body to which the wings remained attached, fly 

 away. But a breeze of wind acting upon the wings 

 of the fly turned round the wasp with its burthen, and 



" Vol. 1. 'id Edit. 330. " lluher, ii. 268. 



