32 



spots of this kind all gradations of withering could be found up to 

 where the entire blade was withered or brown. Plenty of these insects 

 were to be found even where the grass was comparatively dry, bat that 

 they preferred the more juicy grass was shown by their accumulation in 

 shaded places or where the grass presented more vigorous aspect. 

 They could be secured in abundance from patches where no other veg- 

 etation occurred, and in the absence of other insects in numbers to 

 cause the withering mentioned, there can be no question, I think, as to 

 the serious nature of their attacks upon the grass. Even when they do 

 not cause withering of grass they must draw seriously upon its vitality. 



I have thus far been unable to separate any definite broods. Adults 

 occur during the entire year, and larva?, which may be quite certainly 

 referred to this species, may be found associated with them during the 

 most of the summer months. Larva? are perhaps most common during 

 Jane and in August and September, but whether there are two broods 

 or three, or an indefinite number depending only on the length of the 

 season, I can not now say. It seems most probable, however, that 

 breeding goes on irregularly all through the summer months, but that 

 the adults of spring are represented by only two or three generations 

 of progeny, and the members of the latest broods survive the winter to 

 begin the production of new generations in the spring. 



In connection with his description of the species, which was published 

 in 1831, Say makes the remark that "When in the larva state this 

 species is said to depredate on the roots of wheat. Several specimens 

 were sent me by Professor Green in the year 1822, who received them 

 from a farmer in Virginia." 



Considering the wide distribution and great abundance of this species, 

 it seems strange that it should have been so little studied or so rarely 

 mentioned in works on injurious insects. 



The insect is somewhat less than a fourth of an inch long and appears 

 grayish or yellowish gray, and about the most constant marking are two 

 dots on the front of the head, two on prothorax, and two on scutellum. 

 A form lighter than the typical examples bat which seems to me only 

 a light variety, has even these dots obscure or wanting. 



The larva? are light yellowish but seem to be subject to about as 

 much variation as the adults. An extreme form of larva?, probably be- 

 longing to this species, has dark margins to the prothorax and abdomen. 



Several other species of Jassidce have been observed in grass, but as 

 they are not as yet determined I omit farther mention of them at this 

 time. 



THE GRASS-ROOT PLANT-LOUSE ALIAS THE DOGWOOD PLANT-LOUSE. 



(Schi~oneura corjii Fab.) 



Probably the most interesting result of my season's observations 

 from a scientific stand-point, and it may be the most important econom- 

 ically, is the determination of the identity of a form of plant-louse in- 



