i)4 New Yorh- Sidle Ci)ll<(/c (if Forrstrii 



line to posterior concavity, while rcclivaia is figned as straig'lit 

 from tip to concavity. 



Twig scars, Avhicli from association are quite certainly to be re- 

 ferred to this species, show two adjacent curved scars of the usual 

 membracid type. Previous years' punctures on one or two year 

 old twigs are uniform, almost circular, with the surface of healed 

 part deeply blackened and with a narrow fissure at center. Oldei' 

 deformities show much swelling and distortion. A group of these 

 scarred and deformed twigs or branches all apparently to be 

 referred to this species are shown in Fig. 15, photographed by 

 Pivaz from twigs collected at the Forest Camp. 



Aspen is of too little commercial value to make this an im- 

 portant species and nnless it is found to attack other forest trees 

 of the locality it may be considered for this particular region as 

 of little consequence. With other trees involved or with com- 

 mercial use of the aspen wood the species would at once assume 

 economic importance. 



WILLOW LEAF=HOPPER 

 Idiocerus suturalis Fitch 



This insect was frequently observed on willows near the cam]i 

 site, Barber Point, during the summer. Immature forms, col- 

 lected on willow and reared in the insectary, emerged as adults 

 July 12. The species also occurred in considerable numbers on 

 aspen (camp site) during the first week of July and for several 

 days later. The nymphs, mostly of the final instar, present con- 

 siderable variation in markings, usually showing from two to 

 four black spots on the margin of the vertex between the eyes, the 

 inner ones round or slightly angular, the outer ones near the eye 

 elongate — triangular or squarish. In some individuals, other- 

 wise apparently identical, there were two roAvs of quadrate black 

 dots running the length of the body. 



The nymphs live on the leaves, move about quite actively, occa- 

 sionally jumping if disturbed. The leaves show numerous 

 blackened or browned spots which are apparently due to the feed- 

 ing punctures. A few badly infested leaves were entirely brown. 



ASPEN LEAF HOPPER 

 Idiocerus lachrymalis Fitch 



Adults and nymphs (Fig. 38) were collected on aspen July 2, 

 1920, the latter with head markings resembling mature forms with 

 two large black spots, borders next eye, two small round spots near 

 hind border and spots in hind border, two large transverse spots on 

 pronotum, a large black spot rounded behind, divided by narrow 

 line, on mesothorax ; base of metathorax between wing pads black ; 

 margin of abdomen dark, leaving ovate central disk greenish ; 

 below black margined, disk of abdomen greenish, segments five 

 to seven black. 



