BIOLOGY OF THE MEXICAN COTTON BOLL WEEVIL. 7 
bolls being collected under similar field conditions. These records 
were continued throughout August and to the 1st of September. 
Table II shows the results of this examination: 
TABLE II1.—Record of weevil infestation in green bolls of sea-island and upland 
cottons, Madison, Fla. 
] 
| | Upland cotton | Sea-island cotton 
bolls. 
Total 
num- 
Date of examination. a Nee NGane 
exam- Nome ber Re ber 
ined. clean pede clean ured 
1917 
Tunlyail Quer ners series cee anne ee cde cen eae 200 91 9 74 26 
UU Pie hes oe OSU AR CEB ARES a od esaES BEaaRC ou Gar EE Seema mae 200 89 11 81 19 
SEB A ayaa cee en ye neh eee oes hase 200 92 8 69 31 
PANTS eas eres ame eee RAE Saw mee Meee NEAT 5 eo eetems 200 92 8 69 31 
INUVS SG a oe Bs Se Ere Sn ep ee ae er 200 91 9 39 
INTRA DRS 2 5 ses CTE a a NE Eee ee a ie N= 1600 36 64 2166 3 334 
SED Fads Sac o GHGS S OBE OSes Baten wet ws cL Reeaaiene aa aes ie 200 38 62 29 71 
AWE Y EET I pt x hc Slle ea eRe (LN pateaee a Ne AG Rage Oy, Rea SIRES Ua 1,800 529 171 549 551 
Pe CeMt pun CtUned seeps eae sete see Dae ene Nese mace astro ce ata o Samiercsars Pe ESS ees 50. 09 
1500 sea-island. 233 per hundred. 367 per hundred. 
A careful study of Table II shows that the number of weevils 
attacking sea-island bolls was far greater than the number attacking 
upland bolls. Observations in the field also show that a great many 
more weevils are to be found feeding on the sea-island bolls than on 
upland cotton bolls. 
LONGEVITY OF ADULT BOLL WEEVILS ON UPLAND AND SEA- 
ISLAND COTTON. 
The length of time adult weevils live on upland cotton has been 
determined for several different times and places. The object of 
the longevity tests at Madison, Fla., was to determine whether there 
was any considerable difference in the length of life of weevils fed 
on upland and sea-island cottons. 
Table III gives the observations on the longevity of the weevil 
when fed upon different parts of the upland cotton plant. The 
maximum longevity of 84 days was shown by a male weevil that had 
hibernated over the preceding winter and emerged from hibernation 
during the month of April. The average longevity for hibernated 
weevils without food was 12.7 days, compared with an average of 
18.8 days for hibernated weevils fed on cotton plantlets. Adult 
weevils of the first and second generations lived an average of 24.3 
days on cotton squares and 12.3 days on green cotton bolls. 
Table IV gives the data concerning the longevity of boll weevils 
on sea-island cotton. The maximum longevity on sea-island cotton 
