Microscopicai, Essays. 



381 



take them. M. Reaumur made alfo< fome experiments upon the 

 reticulated eyes of bees> which were all taken from the fame 

 hive. He fpread upon them a covering of dark-coloured varnifh, 

 and fhut them up with fome of their companions which had not 

 been touched, in a large powder-box. At about eight or ten 

 fteps from the hive from whence they were taken, the cover of 

 the box was taken off; thofe which had their eyes clear imme- 

 diately took their flight, and went to their habitation ; thofe 

 whofe eyes were varnifhed made no hafte to- get out of the 

 box ; they had fome difficulty to determine themfelves for flight, 

 and the greater!, number directed it at random,, and on different 

 fides, and went not far. To oblige fome of them to fly farther, 

 they were thrown into the air ; they raifed themfelves vertically 

 till they were loft, and not one of them feemed to know the way 

 to its hive. 



To know what would happen if the ftemrnata were covered, 

 he put varnifh upon them, in the fame manner as was done to the 

 reticulated eyes, and let them like wife at liberty, about three or 

 four fteps from the hive ; not one feemed to know it's way, or 

 even feek it. They" flew on all fides upon the plants, but did not 

 fly far,, 



-An infect is, I believe, never found with both kinds of eyes 

 but when it is in it's perfect ftate. The moth, for inftance, which 

 hasfeveral thoufands of eyes in the reticulated form, has only fix 

 fmall fmooth eyes in the ftate of the caterpillar. The wonderful 

 anatomift of the cofius has (hewn, that the eyes of the latter are in 

 the form of a cup, and that the cornea, which is the cover to this 

 cup, is very tranfparent. He has been enabled to clifcover a true 



optic 



