35 



average length of life of those kept entirely ui)on leaves was over 30 

 days. These results show clearly the ability of many of the weevils 

 to live upon foliage alone in fields in which fall grazing is practiced 

 until it becomes sufficiently cold for them to go into winter quarters 

 (see PI. IV, fig. 25). 



LENGTH OF LIFE WITH SWEETENED WATER AND WITH MOLASSES. 



So much has been said al)Out the attraction of molasses for the 

 weevils that tests were made with a cheap grade of molasses diluted 

 with from 20 to 25 j^arts of water to see Mdiether this solution really 

 served them as food. The weevils used were just adult and had taken 

 no other food. They fed quite readily upon the solution, remaining 

 quietly with their snouts in the wat«r for from a few minutes to an 

 hour and a half at a time. The solution did not seem to draw them 

 from anj^ distance, but as soon as a weevil came to it it would stop to 

 drink. Feeding or drinking took place daily or oftener until the 

 deatli of the weevils. The average length of life for the 12 weevils 

 used was a little less than days. 



As weevils without food but with water lived an average of 5^ 

 days, the conclusion is that a solution of molasses 1 to water 25 parts 

 does not serve the weevil as food, since it does not noticeably jirolong 

 life. 



Six weevils just emerged kept upon undiluted molasses showed a 

 greater length of life, these dying at an average age of 11 ^ days. 



LENGTH OF LIFE WITHOUT FOOD, BUT WITH WATER. 



These observations were made during August as a check upon those 

 without water. The 8 weevils used were just adult and had never 

 fed. Each weevil drank for one or two minutes at least once each 

 day so long as it lived. All died at nearly the same time, having 

 lived for an average of about 5^ days. As those without water lived 

 an average of 5 days, it appears that access to water in the absence 

 of food does not materially increase the length of life of the starving 

 weevils. 



LENGTH OF LIFE WITHOUT FOOD OR WATER. 



Three series of observations were made along this line. In the first 

 the weevils used were taken immediately after emergence and never 

 allowed to feed. Fifty weevils were tested in this way during July 

 and August and showed an average length of life of 5 days from the 

 date of emergence. A few lived as long as 8 or 9 days. These never 

 acquired as dark a color nor as great a degree of hardness as is normal. 



In the second series the 15 weevils used were 7 weeks old and full- 

 fed at the time of beginning the test. These showed an average length 

 of life of slightly over 6 days, the range being from 5 to days. These 

 weevils were tested during the latter half of November, and the late- 



