go ANATOMY AND PHYSIOLOGY. [Ch. ii. 



achromatic object-glass ; next an empty space surrounded 

 with dark pigment, which is convex within Hke the neck 

 of a vase, so as to narrow the passage for the rays to 

 about one-half the diameter, or one-fourth the superficial 

 space ; and lastly a longer conical lens, convex at each 

 end and communicating with the optic nerve. The 

 simple eyes, or stemmata, on the contrary,' are as strictly 

 simple as their name implies, consisting of one nearly 

 globular lens apiece. 



The construction of the eye for seeing objects best at 

 a moderate distance will account for the fact that bees 

 mount high up into the air after collecting their store of 

 food, and then, having determined the point, no matter 

 how far off, they fly homewards with the directness of a 

 cannon-ball, and alight at the door of their own habitation, 

 though the country around may be crowded with hives ; 

 but on reaching the entrance their vision appears de- 

 fective, for they then feel their way with the antennae as if 

 totally blind, and should the hive have been moved a little 

 they will rise again into the air to obtain a more dis- 

 tant view, suited to the lengthened focus of their sight. 

 When a stock or swarm is brought from a distance the 

 bees do not take their departure at once, but reconnoitre 

 awhile, visiting surrounding objects so as to well know 

 the spot again in order to return thereto. 



The distinct purposes of the two different kinds of 

 eyes may not perhaps be yet determined with certainty, 

 but Pastor Schonfeld (whom Von Berlepsch employs to 



