ENTOMOLOGY 261 



The scale is quite large, slightly longer than wide, and quite 

 convex, with a prominent ridge or canna down the middle of the dor- 

 sum, and two transverse ridges, the three ridges forming a rough 

 imitation of the letter H. The sides of the scale are quite flaring, 

 and more or less corrugated. Altogether, the dorsum presents a very 

 rough appearance. In color this scale is very dark brown to almost 

 black. 



The females of this species seem to be more than ordinarily pro- 

 lific, even for scale insects. Dr. Coquillet reports having counted as 

 high as 2,200 eggs and young larvsB from a single female. It is 

 probable, however, the average number will be somewhat less than 

 this, as out of a dozen specimens examined by the writer, in no case 

 were over 1,200 eggs found, and usually less than that. The first 

 eggs begin hatching, however, sometime before ovipositing is finished, 

 and therefore it is possible for a considerable error to be made in es- 

 timating the number of eggs actually produced. The young, after 

 hatching, remain for a short time beneath the mother scale, and then 

 crawl out and begin feeding. Unlike most other coccids, this species 

 never, or at least not until quite late in life, loses the power of loco- 

 motion, but is able to change its location at will. They feed either 

 upon the leaves or stems ; palm leaves have been observed almost com- 

 pletely covered with them, and the dirty black fungus which accom- 

 panies them. Happily, the life cycle of this insect is a long one, one 

 generation requiring almost a year to complete its cycle. The egg- 

 laying period for a single female stretches over several months, and 

 the hatching of her eggs covers a like period, so that one will find 

 crawling larvae upon the plants at almost any time. For this reason 

 it is extremely difficult to obtain accurate data in regard to the exact 

 length of any period of the insect's life. 



The black scale is by no means as general a feeder in the green- 

 house as some of those previously mentioned. It confines its attacks 

 principally to the citrus trees and palms, but may, at times, be found 

 infesting rose, oleander, Ficus, Euonymus, Cycas revoluta, and pos- 

 sibly others. (Bui. 119, Md. E. S.) 



The Black Aphis of Chrysanthemum. The black aphis, or 

 "black fly," as it is erroneously called by most florists, is too well 

 known to warrant a detailed description here. Wherever chrysanthe- 

 mums are grown it will be found sucking the sap from the steins 

 and leaves. The insects gather about the terminal buds upon the 

 young growth, and, if neglected, soon become so numerous that the 

 growth of the plant is completely stopped. The rate of increase is 

 almost incredible, and has led some growers to believe that the pest 

 is a product of spontaneous generation. Some observations taken by 

 the writer will serve to illustrate the remarkably rapid rate of in- 

 crease in this species. Young agamic (that is, non-sexual) females 

 isolated upon separate plants, began producing young in every ca^e 

 within eight days after birth. Each female produced from four to 

 sixteen young lice per day, and the average number produced by 

 each was about two hundred. These young lice all insert their beaks, 

 and begin drawing sap almost immediately after birth, and without 



