a: 
12. 
13. 
14, 
155 
16. 
gfe 
18. 
cD. 
20. 
21. 
22. 
23. 
Producing spindle-shaped galls up to 1 inch long. On 
slippery elm leaves. Insect 1 to 114 mm. long, reddish 
Gobaishia ulmifusa 
Galls not spindle-shaped. On various elms .......................... 
Causing leaf curl or root swellings... Eriosoma 
Causing cockscomb or pouchlike galls on upper surface 
Olpleave ste Meta Aik) Secs Eh iitaale usty lak pence ee, « 
Pale yellow, translucent, or head greenish-black and 
abdomen and thorax dark green, covered with white 
waxy powder. On leaves of slippery and wych elm, 
producing cockscomb or pouchlike galls on upper 
SUPT ACCR Rie etree tec et By SE OTN Colopha ulmisacculi 
Olive green to dark olive brown or reddish-brown; 14 to 
114 mm. long. On leaves, causing only cockscomb galls 
ON: WOPCLRSUT LACEY ia an = eek aS Colopha ulmicola 
On apple or serviceberry, causing leaf curl and leaf 
swellings. About 2 mm. long; yellowish or brown to 
reddish, usually with white or bluish flocculence 
Eriosoma 
On other hosts .... Wp eC ee Se ark. agile ie 5 ee ac 
One pop laine =: ne ean eh Se Sees Ole ee eee ey | 
Omngnwieclnave le tome te. eet he ee ee ae! 
Causing convolute galls at tips of branches. Insects 1 to 
4 mm. long; head and thorax black, abdomen pale; 
oviparous female with head, thorax, and abdomen 
goldens vellowrr oes | ois. ee ee Mordwilkoja 
Occurring on leaves and petioles, causing galls at base of 
leaf, juncture of leaf and petiole, or on petiole. Insects 
1 to 3 mm. long; greenish or yellowish-green to 
greenish-white, head and thorax usually dark; body 
OL LEN DIUNIMOSCLL ent is eee le rise: Snell, Pemphigus 
Causing conical galls on upper surface of leaves. Insects 
1 to 2 mm. long, pale yellowish to greenish 
Hormaphis 
Causing spiny galls from buds on stems. Insects 1 to 
2 mm. long, pale yellowish to greenish 
Hamamelistes 
QnecOmiueLrs os ee a eee 
On=hardwoods: <2. 28... ft 
Onepinews. he ee eS USE VRC L RAS FRc es ee ates 
Grr ouhereconibens: «visi foe ea Ne ee ee 
Small, dark insects covered mith white flocculence. Oe 
curring on trunks and branches of Austrian, Scotch, 
IGM bep DINCs eee Soret ace h ye ie canons Pineus strobi 
Insects not covered with white flocculence, at most 
pruinose. Occurring on twigs, branches or leaves _ 
Shining black with white powdery spots on sides and 
white median dorsal line; legs black; body hairy, hairs 
long and stiff. On branches and twigs of white pine 
Cinara strobt 
Noteassabove. 2. 
Olive brown, body nents « sparse at cuvinabike. On leaves 
of Scotch, ponderosa, shortleaf, and white pine 
EFulachnus rileyt 
13 
14 
29 
21 
23 
