270 new yoek state museum 



The Scukfy Bakk-louse 



This scale-insect, known to science, as Ohionaspis furfurus 

 (Fitch), is quite common in the State of New York, where, it is 

 believed to be more numerous and more injurious than in any other 

 of the United States. I have recently seen an orchard of the 

 Kieffer pear, in Columbia Co., ~N. Y., in which the trunks, of from 

 three to four inches in diameter, were so thickly coated with the 

 scales that at a little distance they appeared as if they had been 

 whitewashed. 



The scale, as it appears- when scattered over the bark, and the 

 male and female scales magnified, are shown in Fig. 2 of Plate I. 

 The young larva, the mature female, the male pupa, and the male, 

 are represented in Figure 3 of the same Plate, which has been pre- 

 pared under the supervision of Mr. L. O. Howard, of the Entomo- 

 logical Division at "Washington, to illustrate the insect in his article 

 on the " Scale Insects of the Orchard " shortly to appear, and kindly 

 furnished for use in this Bulletin by consent of the Department of 

 Agriculture in advance of its own publication. 



Dr. Fitch has described so faithfully the appearance of a badly 

 infested tree and of the scale, that his account is transcribed here- 

 with : " The bark of the limb [pear tree] was covered with an 

 exceedingly thin film, appearing as if it had been coated over with 

 varnish, which had dried and cracked and was peeling off in small 

 irregular flakes, forming a kind of scurf or dandruff on the bark. 

 In places this pellicle was more thick and firm, and elevated into 

 little blister-like spots of a white and waxy appearance, of a cir- 

 cular or broad oval form, less than the tenth of an inch in diameter, 

 abruptly drawn out into a little point at one end, which point was 

 stained of a pale yellowish color and commonly turned more or less 

 to one side." This refers to the female scale, shown in enlarge- 

 ment at c of Figure 2, Plate I. The male scales, which usually 

 congregate by themselves (enlarged at d in same figure), are only 

 from one-fourth to one-third as large, narrow, usually straight, three- 

 ribbed, and of a snowy-white color. The eggs found beneath the 

 scales are of a purplish-red color. They hatch about the first of 

 June. 



This scale attacks the apple, pear, black cherry, choke cherry, and 

 mountain ash. I have recently found it abundantly on the Japan 



