33^ CONNECTICUT EXPERIMENT STATION REPORT, 1 900. 



surface; while the canker worm eats any portion of the leaf 

 except the principal veins, but does not puncture the leaf. The 

 White-Marked Tussock Moth, Notolophus leucostigma, Sm. 

 and Abb. ; the Forest Tent Caterpillar, Clisiocampa disstria, 

 Hiibn. ; the Fall Web Worm, Hyphantria cunea, Drury, and 

 the Bag Worm, Thyridopteryx ephemerae for mis, Steph., all of 

 them pests in other places, are also found in New Haven, but 

 up to the present have not been so abundant as to be troublesome. 



(b) Sucking Insects. 



Elm Scale. Gossyparia ulmi, Geoff. 



This insect, shown in figure 6, Plate X, was introduced from 

 Europe and is now distributed over the United States. It 

 collects in clusters at the forking of the twigs and in the crevices 

 of the bark, mostly on the under side of the branches, from 

 which it sucks the sap for its food. The females, dark brown 

 in color, with margins of a white woolly substance, are oval in 

 outline, about an eighth of an inch long and bring forth their 

 young alive instead of laying eggs. They exude a sweet sticky 

 substance, known as "honey-dew," in great abundance and this 

 often drips upon the ground and walks, under badly infested 

 trees. The young appear about the middle of June. The 

 branches which they attack generally die and the whole tree is 

 weakened. 



The Cottony Maple Scale. Pulvinaria innumerdbilis, Rathv. 



This insect may be found on nearly every street in this city 

 where there are maples. One of the worst infested trees stands 

 on the corner of Wall and Orange Streets. White masses of a 

 waxy material, resembling cotton, are seen in the crevices of 

 the bark and on the under sides of the leaves and branches. 

 The impregnated females live over winter on the under sides 

 of the twigs and produce eggs under the cottony substance. 

 They then shrivel and die. The eggs hatch in early summer, 

 the young lice crawl about for a few hours, then settle along 

 the mid-ribs of the leaves, where they continue to suck the sap, 

 until mature, when they migrate to the twigs and there pass the 

 winter. 



Much damage has been done in various places by this insect, 

 but it is easily controlled by remedial treatment. 



