THE ROSE APHIS. 5 
Because of the feeding of this rapidly reproducing insect, the flowers 
may be largely spoiled for decoration, or, since the rose aphis, like 
all aphides, secretes a sweet sticky liquid called honeydew, the appear- 
ance of the foliage may be ruined because of the sooty mold that 
develops where this honeydew has collected. 
HABITS. 
About the time the wingless females become ready to reproduce 
they leave the parent colony and crawl or migrate to various parts 
of the rosebush. Upon finding a growing twig or bud, the female 
settles down with the head pointed toward the ground and begins 
to feed. In a day or two she begins to give birth to young, which 
ordinarily range themselves close together around the tender bud 
or stem behind the adult, and with the heads all pointing downward 
begin feeding. (PL, II.) As the stem or bud becomes crowded 
many move out until the flower itself is covered with them. As the 
aphides continue feeding a large amount of honeydew is produced 
which falls to the leaves beneath, causing a disagreeable stickiness 
on the leaf, which either becomes covered with dust or black from 
sooty mold. 
A very slight jar causes the aphides to let go with one pair of legs, 
and all begin to twitch from side to side on the remaining four legs 
until quiet is restored, while a severe jar causes many to fall to the 
ground. A number of the young develop wings, and when mature 
they fly to other buds and form new colonies. 
When the nymph changes to the winged form the skin splits 
along the dorsum and the adult crawls slowly out. When newly 
transformed the adult is light reddish or green in color, with antennas, 
beak, legs, and cornicles whitish or hyaline, and the wings, which are 
also white in color, appear as little sacks on the back. In about 
20 minutes the wings become fully expanded, and two days later the 
aphis has the colors of the mature insect. 
LIFE HISTORY AND REPRODUCTION IN CALIFORNIA. 
In a climate as mild as that of southern California this insect 
reproduces continuously throughout the year and undoubtedly is 
capable of reproducing asexually and viviparously for an extended 
period. While under observation it has been found giving birth to 
living young throughout the entire year, and the writer has been 
unable to find eggs during the same period. It may be that in a 
climate such as exists in that part of the country, where very cold 
weather does not occur and where the roses continue to grow all 
