23 



tapering gradually toward the anterior end and presenting the appear- 

 ence shown at fig. 17. It was composed of four strongly rounded 

 longitudinal ridges. 



On June 13 the larvae began to hatch, and thus we have the life round 

 completed. 



Summarized, then, the life history is as follows: The eggs hatch in 

 June from the ovisac of the females attached generally to the under 

 surface of the leaf. The larva? cast two skins, and in the autumn — late 

 in October — crawl to the twigs, where they hibernate. In the spring 

 they begin to grow. The males issue in May, fertilize the females, which 

 toward the end of May migrate to the leaves, extrude their ovisac filled 

 with eggs, from which the young begin to hatch in June once more. 

 There is probably a spring moult of the larvae, but this was not observed. 



In none of the occurrences which we have noted above, except in the 

 one at Dothan, Ala., has the insect been so numerous as to cause much 

 damage. Mr. Malone stated in his letter of May 25, 1899, that one of 

 his trees was in places literally covered with the insect, which had 

 caused a number of twigs and smaller side limbs to die. 



Natural enemies. — The only enemy observed in Washington is one of 

 the ladybird beetles (Hyperaspis signata Oliv.), which was received in 

 the larval condition from Knoxville, Tenn., feeding on the scale. 



From the specimens of this scale collected by Mr. Pettit at Ithaca, 

 N. Y., in 1893, he reared six parasites, which were sent to the writer for 

 determination. They proved to be Chalcidids {Aphycus hederaceus 

 Westw., Aphycus flavus How., Coccophag us fraternus How., Pacliyneuron 

 altiscuta How., and Chiloneurus albicornis How.) and a small fly (Leu- 

 copis nigricornis Egger). The same Coccinellid (Hyperaspis signata 

 Oliv.) was also reared by Mr. Pettit. 



Remedies. — There is always a chance that it may be desirable to use 

 some remedial treatment against this insect, as at any time it is liable 

 to increase in numbers and become more or less destructive. A strong 

 whale-oil-soap wash during the winter will undoubtedly kill the hiber- 

 nating individuals, and any treatment which will cause a premature 

 falling of the leaves will be efficient as greatly reducing the numbers of 

 the insect. The use of its leaves to a tree is practically completed 

 some little time before the leaves really fall, and therefore knocking 

 them off with a strong stream of water, or spraying with a strong 

 kerosene-soap emulsion which may even kill the leaves, will do no 

 harm at this time and will kill the insects. 



