48 THE PLUM CURCULIO. 
TaBLE XI.—Combined weekly egg-laying records of all beetles of the plum curculio for each 
locality and percentage of eggs deposited within two, four, six, and eight weeks from 
confinement. 
g 3b Total number of eggs laid each week by all beetles of cS 
roy . ene *] 
s the respective localities. = 
Localiti Be Eg 
ocalities. Seo » so 4=| a re] a a alo! bo 
2 D4 oi Hid | Cad | odd | PAd | Bad | OM ng wo Bo 
HL,/28/88)/28)/s8/4-8] K%S] e238 /S58 |.5a9)] S 
S8|/~p/SE/|SE| ofl =F |-5] 52/22 |SRoo 6 
Ze | & n a Gy cs io) n io) i] B 
College Bark, Md2:2---------- 9| 496| 760 | 414] 289] 192 98 46 23 153 2, 471 
Youngstown; Ni. Yor --eeeeea 8 | 192} 186] 201} 234] 204] 140 68 37 32 1,294 
North) Hast, Basessssseee ose 10 81 | 183 | 197 94 54 48 18 66 46 787 
Washington, D.C........-.-- 4} 232) 213 | 242] 153] 128} 108 81 21 46 1,224 
Myrtle: Gantcaa eae seeesee oer 9 58 62 41 | 176 50 83 48 40 130 688 
Siloam Springs, Ark.....-.--- 29 254 300 343 673 619 545 536 | 350 1,104 4,724 
Douglas Michae---—a-seee = ee | 18 72 | 259 | 329 | 423) 229 89 13 | sacecaleeseeee 1,414 
MOtalldc casos seen aoe eee tease 1,385 |1,963 |1,767 |2,042 |1,476 |1,111 | 810) 537] 1,511 | 12,602 
P : 
Reaeiieri|| Mining eereriae ercentages of tore eges deposited by 
number of | numberof, number 
Localities. eggs per eBEs Det of aes 
mdivid-") iadivid-" per me! | Second | Fourth | Sixth |) eaehom 
ual. ual. vidual. week, week. week. week. 
College Park, Md:--......5.-5- 436 62 274. 55 50. 82 79. 27 91. 01 93. 40 
Youngstown, N. Y.......-.-- 257 72 161. 75 29. 21 62. 82 89. 41 97. 52 
INorthebasin Rass eee seer eras 122 48 78. 70 33. 54 70. 52 83. 48 94.15 
Washington; Dii@2e-)-2------ 557 126 306. 00 36. 35 68. 62 87. 90 96. 24 
Myrtle Gaia .tot snc ce sai 154 1 76. 44 17. 44 48. 98 68. 31 81.10 
Siloam Springs, Ark........-- 388 4 162. 76 11.71 33. 21 57. 83 76. 58 
Douglas) Mich <=... <-.5-+---- 201 25 78. 56 23. 40 76. 59 99. 08 100. 00 
Averages for all locali- 
tikslicomibined!s.22 5. |teeee ela wee 144. 85 26. 56 55. 04 Wiwo2 88. 00 
LENGTH OF EGG STAGE. 
Little exact information as to the period of incubation of eggs of 
the plum curculio is to be found in the earlier accounts of this insect. 
Trimble (Insect Enemies of Fruits, p. 29) states that if the weather 
be cloudy and cool, a week or 10 days is required for the eggs to 
hatch, but that in very hot weather the young grubs will escape in 
4 or 5 days. Riley and Howard state that from 3 to 10 days are 
required for the egg stage, depending upon the weather. Other 
writers have given about the same periods. In 1904, in Illinois, 
Crandall determined the length of time required for hatching of 6 
eggs as approximately 44 days for 4 and 4 days 9 hours for the other 
two. His observations were made on eggs kept under laboratory 
conditions. 
