392 JOURNAL OF ECONOMIC ENTOMOLOGY [Vol. 15 



1. A pint of blackeyed cowpeas in a quart Mason jar were ovi- 

 posited upon by a few females on September 21 and 22, 1920. On 

 Septem.ber 22 about a thimbleful of mercury was sprinkled into the 

 jar and the lid screwed on. Shortly after a paraffined rubber ring 

 was put on to exclude mites (Pediculoides ventricosus), but this was 

 removed October 18. The beans were examined November 5. They 

 were spread out and examined carefully with a reading glass. In- 

 festation being light, only forty (40) eggs were found, and these were 

 examined under the binocular. No embryos had developed. Marked 

 preference was shown by the parent weevils for blackeyes with fewest 

 wrinkles. 



2. September 20, two thimblefuls of mercury were placed in a small 

 vial with a hole in the cork and the vial placed upright in a pint of 

 blackeyed cowpeas in a quart Mason jar. Twenty-three (23) B. 

 quadrimaculatus were put in the same day. More weevils were put in 

 September 22. Shortly after, a paraffined rubber ring was put on the 

 jar; this was removed October 18. Examination of the beans was 

 made on November 5, the beans being gone over carefully with a 

 reading glass. One hundred thirty-five (135) eggs were picked out and 

 examined under the binocular with the result that no embryos were 

 found to have developed. 



3. Twenty -two blackeyed cowpeas with thirty -nine (39) newly- 

 deposited eggs were put in a small vial with one thimbleful of mercury. 

 These eggs were ^aid September 20-23 and were put in the vial with 

 the mercury on the 23rd. The vial then was sealed with a paraffined 

 cork. Examination on November 5 showed that no embryos had de- 

 veloped, the eggshells being dry and empty without exception. 



Small spots of black mold were found on the beans in all the con- 

 tainers. The paraffined rings and cork were thought advisable to 

 exclude mites, but may have influenced the results. Later duplica- 

 tions of the above experiments, without using paraffin and rubber 

 rings gave the same results, as far as the failure of the eggs to develop 

 is concerned. In these no mold appeared. 



On July 22, 1921, several weevils, B. quadrimaculatus, were put into 

 a quart Mason jar of clean red ripper cowpeas. The next day, after 

 oviposition had taken place freely, the eggs were examined with the 

 aid of the binoculars, and all eggs that were not properly glued to the 

 seed coat or that appeared to be imperfect in any way were discarded. 

 One hundred (100) were placed in a vial, 3.2 x 10 cm. and an equal 

 number was placed in a similar vial. These eggs were perfect as far 

 as it was possible to determine. Into one vial was placed a little 



