March, 1902,] Remarks on Study of Leaf-Hoppers. 225 



easily by the thumb are most convenient), and captures from 

 different plants may then be kept separate, or in case of a large 

 catch, one bottle may be put aside for the insects to quiet down 

 while others are caught in another bottle. When certainly dead 

 it is well to transfer them to small pill boxes, noting plant from 

 which they are taken on the box. If the bottle becomes moist it 

 should be kept from wetting the insects by inserting a little blot- 

 ting paper or absorbent material, as the delicate species will be 

 ruined by too much moisture. To keep separate all the species 

 that may be collected on a large number of plants may require 

 many tubes and boxes, but the data thus secured is worth the 

 effort and the memor\- should not be trusted for such data, at 

 least until the species are well known. 



As soon as convenient after the insects are dead they should be 

 sorted over, separating, if desired, the various species, and if to 

 be packed for examination at some later date or for transmission 

 by mail, they should be put in pill boxes in thin layers separated 

 by soft paper, the box being filled so that no rattling is possible. 

 The papers may be cut to just fit the box and in this form data 

 may be recorded on each slip to apply to the insects beneath it. 

 Care should be taken that specimens of the different layers may 

 not possibly become mixed. If the specimens are to be studied 

 or mounted the}- ma}- be spread out on white paper and protected 

 temporarily b}' covering with a bell jar. 



Some of the largest species may be pinned after the usual man- 

 ner, but the most satisfactory method of mounting is to glue the 

 insect on a paper "point," which is supported on an ordinary 

 insect pin. The head of the insect should be directed forward 

 when the point stands to the left of the pin and the label or 

 labels with localit}', date, collector's name and the food plant, 

 when known, placed beneath. The best effect is gained by pin- 

 ning through the right hand edge of the label and pushing it up 

 to near the point when the left hand edge should be about equal 

 to the point or project very slightly be^-ond it. I use points 

 about 8 or 9 mm. long, just wide enough at base to hold the pin, 

 and place them uniforml}- about ten millimeters from the head of 

 the pin. When arranged in series of four abreast comparison is 

 eas}' and points of difference are quickly noted. 



The parts most used in classification may be illustrated in the 

 accompanying figure. On the dorsal part of the head, shown at 

 c, the space within occiput, eyes and anterior margin is the vertex, 

 the part shown back of the head is the pronotum the dorsum of 

 prothorax. The front of the head or " face," d, includes a large 

 central portion, the front, and below this is a squarish piece, the 

 clypeus, below which is the minute labrum resting on the beak. 

 At each side of the clypeus is a well defined area, oval or semi- 

 elliptical in shape, the lora, between which and the eye is the 



