JAPANESE SPECIES OF PERNICIOUS SCALE. 



171 



The male insect of the allied species has an anterior half of the thorax 

 more stout and widened than the pernicious scale and the number of 

 the antenna! segments differ also in the two related species. Further in 

 the pernicious scales, there is only one, while in the allied scales there are 

 two transverse colored hands on the dorsal surface of the thorax. + 



The newly hatched larva of the pernicious scales 2 looks to hear two 

 long caudal filaments, each on the tip of the mesal lohes, while in the 

 allied species they are grown in the space lying between the lobes. 



The above mentioned differences between the two kinds of scales, 

 lead us to conclude that the subject of this paper can not be considered as 

 the same with the pernicious scales; but I should say it may be very 

 nearly related to the latter, or rather a variety of the same. If our allied 

 scales are not same with the pernicious scale, the original home of the 

 latter should not be Japan, but may be China, Australia or some 

 Pacific islands. 



Injuries of the Allied Species. — Till now, I could only find them on 

 the apple and pear trees in our country hut not on any other. On the 

 apples, they are usually found much less than on the pear trees as most 

 of our fruit growers are quite ignorant of their harm. Even on the pear 

 trees, their injuries are comparatively less than I have imagined before ; 

 but I have detected, however, on rare occasion, in certain localities, a few 

 young pear trees were entirely destroyed by the insects. The facts that 

 the allied scales do not rapidly increase and their harm is only limited in 

 a few localities seem to depend upon the presence of the parasites, 

 which devour very voraciously a large number of the scales. The principal 

 enemies against the allied scale are a red mite, Coccinella Japonica, 

 Thunb, and a chalcis fly. 



The latter which I could not examine sufficiently from the wants 

 of specimens, seems to me to be a species of Genus Coccophagus described 



t The characters of the hoth sexes of the pernicious scales referret to, are the works of 

 Messrs. L. 0. Howard and C. L. Marlatt- and of Mr. T. D. A. Cockerell. 4 I regret much 

 that I could not get the access to the Kept. U. S. Dept. Agri. 1830 during my study on the 

 scales. 



