PROCEEDINCiS. VJ'Ii 



Leaves eiirled sin<>-ly, usually (Uie-halt' nf lilailc only 



involved americana 



No leaf eui'l, insect feedini;' on wooly colonies on trunk 



and l>i-anclies only _ rileyi 



On Eiujlisli ihii — ^largin of leaf enrolled usually to midrib 



only, no thickenini;' tissue ulmi 



Whole leaf involved, tissue and veins much thickened. 



becoming' baglike lanuginosa 



The only two galls liable to be confused ai-e those of americana and 

 ulmi, which, although on different specie.s of elm. are very similar. Tiie 

 lice contained, however, are distinguishable both maci'oseo])ii'al|y aiid 

 microscopically. 



The young stages of americana ai-e bluish-puri)le. those of ulmi are 

 green, both covered with a tloeeuleiit wax. The pui)ae of both species are 

 juirple with paler wing pads. Definite determinations may be made by 

 the antennae of tlie winged individuals. In ulmi segment III. being 

 nearly twice the length of IV.+V.+YL, and segment V. is without annu- 

 lar sensoria. while americana has III. equal to IV+V.+VI. and segment 

 V. has annulations. 



Distribution : 



The sjiecics ulmi witli which we are dealing is not a native insect in 

 America, but has been introduced from Europe at a comparatively recen.t 

 date. 



It was first recorded from Maine in 19l:i on elm. but has been seldom 

 recorded from black currant roots in America. 



In British Columbia it was fir.st reported in IM^Jd. when ,Mi-. \V. .\. 

 Ross identified specimens collected by Mr. W. II. Kobertson, Provincial 

 Horticulturist, from black currant roots in a nursery at C'liilliwack. 



In the spring of TJl^l it was located freely on English elm, both at 

 Chilliwack and Agassiz, and notes on its life-history have been taken 

 during' the following seasons : 



LiFE-IIlSTORV. 



The eggs, which are laid in the fall on the elm truid<. hatch betwi'cn 

 Aj^ril I'ltli and 30th, accoriling to the season. The newly eini'rt;r 1 

 nymplis crawl to a bursting bud. often several yards distant, and ensconce 

 on the underside of a young h-af. Tliese individuals become the stem- 

 mothers and remain in the leaf until death. With the feeding of the 

 insects the leaf curls, forming a pseudo-gall in about a week, ami tluis 

 protecting to some extent the lice therein. 



The stem-mother movdts four times and comnu'iu'cs de]iositing young 

 when aliout three weeks old. Approximately tif1\- young are deposited 



