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44 DECIDUOUS FRUIT INSECTS AND INSECTICIDES. 
have been made by the various authors. For northern latitudes we 
are unable at present to form any definite conception as to the number 
of generations. 
LENGTH OF THE LIFE CYCLE. 
The length of the life cycle or developmental period of a genera- 
tion of the lesser peach borer, based on field observations, has already 
been given in connection with Table II. The life cycle of the summer 
generation was approximately 44 months, and of the winter genera- 
tion 7$ months. Fortunately Mr. Quaintance has succeeded in actu- 
ally rearing a single specimen of this insect through its entire cycle, 
in the grounds of the Insectary of this Bureau. On September 5, 
1905, he placed 8 recently hatched larvee in small artificial wounds 
made 3 feet from the ground on the trunk of a peach tree. Each 
larva was placed in a separate wound and the whole then protected 
by a wrapping of paper. By October 1, not quite a month later, 5 
of the larve were found in their respective wounds and had grown 
remarkably, being from a half to five-eighths of an inch in length 
(13 to 16 mm.). On the 24th of the same month, or just over a 
month and a half after hatching, the five larve were still alive and 
were either about to molt or had just done so; three of them measured 
13 mm., one 16 mm., and the fifth, 19 mm., averaging about 15 mm. 
The following spring, on April 5, 1906, another examination was 
made, and it was found that 4 of the larve had perished. The re- 
maining one was inactive, but began to feed voraciously five days 
later, and by about April 13 had formed its cocoon and pupated. 
The moth, a male, emerged on May 14, 1906. 
The lengths of the respective stages: for this individual were as fol- 
lows: Egg, 74 days; combined larval instars, 220 days; pupal instar, 
31 days; making a total of 258 days, or 8.6 months for the cycle 
(from August 28, 1905, to May 14, 1906). This agrees remarkably 
well with time approximated for the winter generation in the South, 
where the periods of larval inactivity during the cold months are 
naturally shorter, and hence growth is more rapid. The individual 
reared was a descendant of parentS from Fort Valley, Ga., mailed to 
Washington. 
NATURAL ENEMIES. 
The lesser peach borer has a number of natural enemies, nearly all 
of which are parasites belonging to the order Hymenoptera. 
Elachertus n. sp., of the family Eulophide, as determined by Mr. 
E. S. G. Titus, is probably the most common, and is an internal para- 
site which is fatal to the host just before pupation. After the host 
larva has constructed its cocoon the parasitic grubs eat their way 
through its body and pupate nakedly in the host cocoon, entirely 
filling it. As many as 138 of these parasites have been reared from 
= = ome ~ Seeeiin Ab 
