IQQ EXPERIMENT STATION RECORD. [Vol.35 



distance traveled in each field and the number of grubs exposed by the plow, 

 and recording at the same time the distance from the field to the nearest trees 

 upon which the IMay beetles might be supposed to have fed. Observations and 

 collections of this nature were made by six field assistants during 1904, 1905, 

 1907, and 1908 in 549 fields widely scattered throughout central Illinois, and 

 in a few fields also in the northern and southern parts of the State. The total 

 distance traveled was over 429 miles, a total of 12,069 grubs of the genus 

 Phyllophaga and 1,187 of the genus Cyclocephala being collected. 



For the purpose of classification all of the data thus obtained were assorted 

 into four groups, according to the distance of the fields from the nearest 

 trees. In group 1, in which 224 miles were traveled in fields with trees within 

 or on their borders or within less than one-eighth of a mile, white grubs of 

 the genus Phyllophaga were found at an average rate of 39.17 to the mile. In 

 group 2, 40 miles were traveled in fields with trees more than one-eighth but 

 less than one-fourth of a mile away, and in these Phyllophaga grubs averaged 

 17.83 to the mile. In group 3, in fields with trees more than one-quarter of 

 a mile away and less than one-half mile, 130 miles were traveled and Phyl- 

 lophaga grubs averaged 15.94 to the mile. In group 4, in fields with trees half 

 a mile away or more, 35 miles were traveled and 14.4 was found as the average 

 number of Phyllophaga grubs. 



In a study of the data bearing on the kind of crops in which May beetles 

 prefer to lay their eggs, it was found " that more eggs were laid in pastures 

 (84 grubs per mile) than in any other crop; that small grain came next with 

 61 and 02 i)er mile for fields which had been in oats and wheat, respectively ; 

 that fallow land, grown up of course to weeds, largely grasses, was third, with 

 48 grubs to the mile ; that clover and corn seemed not far apart in attractive- 

 ness to the egg-laying beetles — clover with 30 and corn with 25 grubs to the 

 mile; and that meadow crops (excluding clover) were least sought by the 

 egg-laying beetles — about 15 gi-ubs to the mile in fields which had been in such 

 crops when the eggs wei-fe laid. . . . The evidence of the predominance of 

 grasses and small gi-ains over corn and other crops as a lure to May beetles 

 about to lay their eggs is unmistakable here, and much more emphatic than 

 that obtained from our general collections behind the plow." 



Studies of the Mexican cotton-boll weevil in the Mississippi Valley, R. W. 

 Howe ([/. S. Dept. Agr. Bui. 358 (1916), pp. 32, figs. 2).— This is a report of 

 studies carried on during 1913, 1914, and 1915, largely at the Delta Boll Weevil 

 Laboratory at Tallulah, La., with a view to determining what influence new 

 climatic and environmental conditions have upon the biology of the boll weevil. 

 The work has been summarized by the author as follows : 



"In northern Louisiana the average longevity of the boll weevil adults on 

 cotton squares was 54.56 days, on bolls 31.41 days, on cotton leaves 8.17, and 

 on okra fruit 5.4, the average for these different classes of foods being 14.13 days. 

 The females live somewhat longer than the males, there being an average of 

 12.5 days for females and 9.82 for males. 



" A number of weevils were found feeding in okra blooms in the field, but 

 attempts to cause them to breed in okra fruit in the laboratory were unsuc- 

 cessful. A number of eggs were deposited, but they failed to hatch. 



"The largest number of eggs deposited by the first generation weevils was 

 204, the average being 132. The daily maximum varied from 5 to 12. Second 

 generation weevils showed somewhat less fecundity, the maximum oviposition 

 being 175 eggs and the average 69.4. The average period of oviposition was 

 38.2 days, the range being 1 to 77 days. The greatest activity of the weevil in 

 depositing eggs was found to bti between the hours of 9 u. m. and 1 p. m.. but 



