520 



SUMMARY OF CURRENT RESEARCHES RELATING TO 



quickly pushed up the tube, as shown at fig. 108, the end of the tube 

 being closed meantime with the thumb. The captured insect by 

 this means can be confined to the field of view, and all its movements 

 can be conveniently observed in all weathers. The size of the insect 



can also be determined by a divided scale 

 on the top of h. By this process of capture 

 the delicate wings and antenna), and the 

 fine dust and hairs are not injured, as the 

 captive insect is neither held in the fingers, 

 nor killed, nor pierced through. Shy 

 insects, and those that do not readily 

 escape, as beetles and caterpillars, as well 

 also as spiders, can be knocked from the 

 plant into the funnel by the plug. 



It may be here remarked that the roughening of the inside of the 

 tube a is intended for those insects which have no hooks on their feet, 

 to crawl up more easily. Should it happen that, in spite of this, 

 these animals will not move up the tube, it must be held with the 

 eye-piece down and the insect shaken into the tube. After the in- 

 sertion of the plug the funnel is put on the lower end to serve as a 

 foot to the instrument." 



The patentee further says that what distinguishes his apparatus 

 from all others is the following contrivance : — " After observing the 

 captive insect in all its parts from above, it can be observed from the 

 under side, by simply turning the apparatus upside down, so that the 

 insect lies on its back on the mica-plate. If tlie space is increased by 

 withdrawing the plug slightly, and so giving the insect more room 

 for moving, it immediately turns itself over and stands upon its feet. 

 If the plug is again pushed in as far as a — (3, and the apparatus turned 

 with the eye-piece upwards, in a few moments the observer is in a 

 position to examine the insects on the under side. This alternate 

 observation can be repeated at will. If the insect is restless, the 

 mica-plate need only be pressed a little closer, in order to hold it very 

 gently. The space above the plug is adjusted to the size of the 

 insect by moving the ring c c up or down. In order to avoid having 



