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blossom bud. They are very tenacious of life. Those Mr. Hart 

 secured some days after removal from the buds and placed in 

 80 per cent, alcohol at 11:25 a.m., were still active at 2:40 p. 

 m., and lived for some time in the 95 per cent, alcohol in which 

 I then submerged them, but at 3:50 p. m. seemed to be dead. 

 Infested rose plants were fumigated with hydrocyanic acid gas, 

 in one case one tenth, and in another fifteen hundredths of a 

 gram of potassium cyanide being used to each cubic foot of 

 space. The plants were subjected to the gas for fifteen minutes 

 in both cases, with the result that only the larvae that were ex- 

 posed were killed, while such as were protected by the sepals 

 were not affected. The same treatment killed flies (in from 

 twenty to thirty seconds), plant-lice, and beetles. On descending 

 into the ground the larva constructs an almost transparent co- 

 coon — presumably the product of exudation — sufficiently viscid 

 to stick to surrounding particles of sand or dirt, and becoming 

 sufficiently tough to retain its contents. Within this the larva 

 remains two days, some of the time in a curved position, when 

 it passes into the pupa state. The larval period, including two 

 days in the cocoon, is seven days. That moisture has little in- 

 fluence on the development of the insect is shown by the fact 

 that pupation in this case was continued in sand thoroughly sat- 

 urated with water. 



Pupa (Plate III., e, f). — Length, 1.6 mm.; width, 0.53, mm. 

 Color, at first as in the full grown larva, later the eyes are red 

 and the general color of the body more reddish-yellow, but 

 at the time of emerging from the cocoon the eyes are black, 

 the antennae and legs nearly black, and the head and prothorax 

 dusky. On the dorsal abdominal area is a median red space, 

 widest at base, diminishing to the sixth segment. On all of 

 the segments except the first is a transverse spinulose ridge 

 near the anterior dorsal margin, less marked on the second 

 segment and increasing in size to the eighth, which is sculptured 

 somewhat as in the larva. Ventral surface without spinulose 

 ridges. Anal segment much smaller than seventh, which is 

 slightly smaller than sixth. Bases of antennae produced, with 



