FAMILY FULGORIDM 103 



related trees, in August and September or October. The\' 

 may be obtained by l)eating the trees over an umbrella with 

 a stick. The genus includes six or eight common species. 

 They are quite similar in general appearance. 



Delphacidse. — The Delphacidie are characterized by the 

 presence of a large, movable spur on the end of the tibia, 

 and tibia and tarsal joint run out with spines. A specialized 

 appendage for attachment to twigs, stems of grass, etc., 

 enables the insects to jump more readily. This is a charac- 

 teristic structure for this group. These hoppers occur 

 abundantly in low vegetation, especially on grasses and 

 some species are abundant enough to be detrimental, as for 

 instance, the corn Delphacid (Dicmnotroins maidis), and the 

 sugar-cane hopper, which has been extremely destructive 

 in the sugar plantations of the Hawaiian Islands. Our 

 species occur sometimes in blue-grass meadows, and do some 

 damage. They are minute, varying in size from one and 

 a half to two millimeters, to four or five millimeters in length. 

 They present a great variety of modification in wing develop- 

 ment. Some are dimorphic. There are some in which the 

 hind pair of wings are wanting or not full-sized, some in 

 which front wings are reduced entirely or to mere rudiments. 

 This occurs first in the females, but also in some species in 

 the males. The greatest amount of reduction appears to 

 occur in those which live where food supply is abundant 

 and flight becomes unnecessary. There ma>' be a summer 

 generation without wings and a fall generation with wings. 

 One other interesting feature is the fact that they are para- 

 sitized in a peculiar manner. Certain Hymenopterus para- 

 sites deposit eggs on the bodies of these and larva? are pro- 

 duced in a sort of sack extruded between the segments of 

 the abdomen, and within this sac the larva? develop. These 

 parasites may have some value in reducing the number of 

 the hoppers. 



The eggs are deposited in the leaf or stem of grasses, etc., 

 and the larvse hatch from these and feed on the plant 

 attacked. The stages of development are gradual and there 

 are one or two broods annually for the most of the species. 



