746 NEW YORK STATE MUSEUM 



of those forms that can not be controlled by fumigation; and, 

 inasmuch as it is known to have been established in New York 

 city and vicinity for nearly 20 years, it is surprising that it has 

 not spread more rapidly. See pi. 3 for an illustration of the 

 insect and its work. 



Birch leaf bucculatrix, Bucculatrix canadensisella 

 Chamb. Last fall the white birches all about Albany were very 

 badly affected by a small caterpillar which ate away the tender, 

 under portion of the leaves. The skeletonized parts dried, 

 turned brown, and the trees looked much as if they had been 

 injured by fire. This year the pest appears to be even more 

 numerous, having been very abundant about Albany. Its work 

 was also observed all through the western two thirds of Massa- 

 chusetts, and it has been reported as quite injurious in several 

 localities in the northern part of New York. This attack is not 

 unprecedented, though of considerable interest on account of 

 its covering so large a territory. This insect was reported to 

 Dr Lintner as injurious about Scottsville, Monroe co., in 1886, 

 and in 1891 it seriously injured birches about Ausable Forks 

 N. Y. 



The parent of this caterpillar is a little, brownish white moth 

 with a wing spread of but § of an inch. The caterpillar is a 

 delicate, yellowish green creature about J of an inch long when 

 full grown. During the last half of August and the first half 

 of September many can be found curled up under a white, silken 

 covering known as the molting cocoon. Later a beautiful, 

 white, ribbed cocoon will be constructed in which the winter is 

 passed. PI. 4, fig. 5 illustrates well the appearance of the insect 

 in its various stages. 



Valuable trees can be protected by spraying with an arsenical 

 poison, preferably arsenate of lead, taking special pains to get 

 the poison on the under surface of the leaves. It is to be 

 expected that natural agents will soon reduce the numbers of 

 this tiny pest and thus prevent the ultimate killing of the trees. 



Golden oak scale, Asterolecanium variolosum 

 Ratz. White oak twigs received from Yonkers N. Y. Sep. 16 

 were literally covered in places with this insect. The scales 



