152 ORDER HOMOPTERA. 



unless when a fruit-tree becomes infested, in which case all the dead branches may be 

 removed and burned. 



Cicada cANicuLARis. Dogday Harvestfly. (Plate ix, fig. 3.) 



Body black : the head beneath, breast and sides mealy ; top of the head and thorax 



ornamented with olive-green lines connected together so as to form characters, one of 



which upon the thorax resembles the letter W. Legs, front of the principal veins of 



the wing-covers and wings edged with green. The body of this species is thicker and 



proportionally shorter than the septendedm : abdomen of the male tapers raindly. 



Appears late in July, and continues into September. 



According to the observations of Mr. Harkis, this species is very regular in the time 



of its appearance : for many years in succession, it has been heard for the first time at 



Cambridge on the twenty-lil'th day of July, between the hours of ten in the forenoon and 



two in the afternoon. It is therefore an annual visitor, in which respect it differs widely 



from the preceding species, while its other habits are much the same. It deposits its eggs 



in the extremities of the branches of various trees. It is not particularly injurious to fruit 



trees, nor indeed to any other species of vegetation ; besides, it never has appeared in 



sufficient numbers to excite any apprehension of injury. 



Cicada NovEBORACENsis. ' (Plate ix, fig. 2.) 



Body black : veins of wing-covers and wings, thorax and abdominal rings edged or or- 

 namented with orange. 

 This species is smaller than either of the preceding ; but it appeai-s annually, and has 

 the same habits as to the mode of depositing its eggs. It is never in sufficient numbers to 

 inflict serious iiyury to forest or fruit trees. 



Tree-hoppers, Leaf-hoppers, etc. 



Form triangular, but variable in the diflerent genera : eyelets two ; musical instruments 

 none ; locomotion by leaps aided by wings. 



These grotesque insects inhabit the trunks, limbs and leaves of trees : they are small ; 

 colors green, gray, with spots or cloudiness of the wings ; faces often vertical or nearly 

 so, with the thorax and anterior parts thick, whence they taper rapidly to the extreme 

 points of the wings ; legs furnished with spines. The species are very numerous, each tree 

 and shrub being inhabited by its own peculiar kind. 



As this group of insects have habits much the same as the cicadians, and obtain their 

 nutriment by sucking the juices of plants, it is supposed that in some cases they may be 

 detrimental to vegetation : they cannot, however, injure the farmer very materially, 

 though as a class they are quite numerous. 



