THE CALIFORNIA PEACH BORER. 69 
insectary, and to note the development of the eggs. (See. Pl. IX.) 
Oviposition under these conditions was more or nee unnatural, but the 
eggs thus placed developed under perfectly normal conditions. The 
period from oviposition to the time of hatching, as indicated in 
Table I, lasted from 11 to 19 days, with an average of 14 days. There 
were several hundred eggs in each lot. 
Tasie I.—Length of egg stage of the California peach borer (Sanninoidea ovalescens). 
Lot No. | Date eggs placed. | Date eggs hatched. i eg of 
eee WUlys8=9> Sse ox. July 27-28........- 19 
Qesesees WUlye VSR See ot emai Dualyeal . oo aoe ae 13 
Bere ei Uilye20 ies sss ae 3 NCE}, eee ee 4 
Cee ces Tals 212225 kee Augei=4 -eeeesecs 11 to 14 
Dasa jetes|ox5 <r GUS SES seneeoee AUP? 3-62 65-555 <0 13 to 15 
Glee uss “July 23-2480 2, Ate Tie sete de 14 to 15 
In escaping, the larva breaks a circular hole through the micropyie 
or depressed end of the egg and leaves the eggshell attached to the 
tree. The eggshell remains thus attached throughout the summer 
and fall until early winter rains dissolve the glue by which they are 
attached. 
FERTILITY. 
Many eggs gathered from different rearing cages in our numerous 
experiments were noted to determine what proportion was fertile, 
with the results shown in Table II. 
TasLe I1.—Proportion of fertile eggs of the California peach borer. 
Fertile Sterile Fertile Sterile 
Lot No. eggs eggs not | Total. Lot No. eggs eggs not | Total. 
| natched, hatched. hatched. | hatched. 
43 3 46 Boo. dcc. <a se 196 3 199 
42 42 | 85 Qik elec opee = ke 55 0 55 
75 3 | CEST | USS ere es ee 202 3 205 
139 15 154 | 
71 3 74 Potaleenascas-=7 1,225 116 1,342 
204 44 248 || Percentage......:.... 91.28 8.72 100 
198 0 198 
THE LARVA. 
FEEDING HABITS OF NEWLY HATCHED LARV#. 
The newly hatched larve (fig. 22, a) are extremely active and 
move about freely and they may crawl for a considerable distance 
from the egg. After hatching they immediately seek out protected 
places, either by hiding in cracks of the bark or under particles of 
dirt or loose bark, or they go below the surface of the ground and 
then at once begin to enter the tree. 
Newly hatched larve were closely observed many times as they 
entered the bark. We were never able to watch newly hatched 
408°—Bull. 97—11——2 
