68 INSECTS INJURIOUS TO FOREST AND SHADE TREES. 
20. THE ELM GALL-LOUSE. 
Colopha ulmicola (Fitch). 
Order HEMIPTeRA; family APHID. 
Making in June a large excrescence like a cock’s comb on the upper side of the leaf, 
the gall about an inch long and a quarter of an inch high, compressed, and its sides 
wrinkled perpendicularly, with its summit irregularly gashed and toothed, of a paler 
green color than the leaf and more or less red on the side exposed to the sun; opening 
on the under side of the leaf by a long slit-like orifice; inside wrinkled perpendicularly 
into deep plaits and oceupied by one female and a number of her young, which are 
minute oval yellowish white lice 0.02 inch long, with blackish legs; the female more 
or less coated with white meal on her back, 0.07 long, oval and pale yellow, with 
blackish legs and antenne. By midsummer the galls dry up. (Fitch.) 
21. THE WOOLY ELM-TREE LOUSE. 
Eriosoma Rileyi (Thomas). 
Order HeMiIpTERA; family APHID. 
Clustering on the limbs and trunks of the white elm, causing a knotty unnatural 
growth of the wood, small aphides covered with an intense white wool-like substance, 
the limbs at a distance appearing like snow. (Riley.) 
In Illinois and Missouri, late in May and in June, the white elms in the 
larger cities are apt to become infested with these conspicuous and 
curious insects. Riley finds that by washing with a weak solution of 
cresylic acid soap they will be instantly killed. 
The adult is dark blue, the wings clear, three times as long as wide, 
and more pointed at the ends than in H. pyri. Costal and subcostal 
veins, and that bounding the stigma behind robust and black. Length 
to tip of closed wings, exclusive of antenne, 0.12 inch. 
The young lice are narrower and usually lighter colored than the 
adults, varying from flesh to various shades of blue and purple. (Riley.) 
The following insects also prey on the elm: 
HEMIPTERA. 
22. Common elm aphis. Schizoneura americana (Riley). 
23. Yellow elm louse. Callipterus ulmicola Thomas. (VIII, 111). 
COLEOPTERA. 
24, The grape-vine flea beetle. Graptodera chalybea Mlliger. 
25. The goldsmith beetle. Cotalpa lanigera (Linn.). 
26. Magdalis armicollis Say. (Inhabits the elm, Lebaron., 4th Rep). 
LEPIDOPTERA. 
27. Anthaxia viridicornis Say. (Psyche II, 40.) 
28. Synchroa punctata Newman. (Psyche II, 40.) 
28. The American silk worm, Telea polyphemus Hiibner. 
29. The Emperor moth, Hyperchiria io (Fabricius). 
