54 THE FLORIDA ENTOMOLOGIST 
they pass the winter without the production of males and females 
and winter eggs. Watson (36) says that in the warm climate of 
Florida, especially the southern part, viviparous and partheno- 
genetic reproduction will undoubtedly continue all winter in the 
case of the tomato louse, Megowra solani, and also of the green 
peach aphid, Myzus persicae. Considerable work has been done 
by the United States Bureau of Entomology on the southern grain 
louse, Toxoptera graminum, and they have found that it will 
breed viviparously all winter in all southern states. In their 
bulletin on the subject, Webster and Phillips (87) make the state- 
ment that there is no resting or egg stage and whenever there is 
a sufficient food supply and warm weather the aphids become 
very abundant. Hubbard (22) is also of the opinion that the 
southern aphids will live and breed viviparously over winter, 
and says that the males of the orange aphids rarely if ever appear. 
In spite of the fact that several species have actually been ob- 
served living on the plants throughout the winter and that most 
of the workers of this and other Southern States admit the prob- 
ability of viviparous breeding through the winter, it is a ques- 
tion as to where the vast majority of aphids pass the winter. It 
is probable that many, if not all, of those species which live on 
perennial plants or on plants which are fresh during the winter 
will live through the season without producing eggs. Those 
whose host plants die in the fall must find a different host or 
else live over winter in a different form, and it is probable that 
some at least live in the egg stage. A warm spell of weather 
and fresh tender shoots of their host plants will bring out large 
numbers of plant lice which may again disappear under adverse 
conditions. In all probability they produce sexual forms and lay 
sexual eggs when the weather conditions are bad and when their 
food plants die out. 
MYZUS PERSICAE SULZ. 
This insect, commonly called the green peach louse, is probably 
the most common aphid which occurs in this part of Florida, and 
with one or two exceptions the most destructive. The writer has 
found it in more or less abundance at all seasons of the year ex- 
cept during the summer months, and on a great variety of plants. 
It selects the tender shoots of fruit trees, many garden crops, and 
ornamental plants, and when conditions are favorable reproduces 
in large numbers, often becoming very troublesome. They have 
been observed several times abundant enough to cause cabbage 
leaves, and also turnips, collards, and other cruciferous plants to 
