1 Trans. Acad. Sci. of St. Louis. 



Professor LeRoy McMaster gave a review of the ad- 

 dress of Dr. E. A. Schaefer, on the '' Chemical Origin of 

 Life," before the British Association for the Advance- 

 ment of Science. 



Dr. A. E. Ewing gave some of the results of his inves- 

 tigations on the plum curculio : its food, ability to stand 

 cold, inability to stand drought, longevity. 



A series of experiments with the plum curculio, conducted during the 

 summers and the winter of 1908 and 1909, showed that the fruit of the 

 plum or of the peach tree is not essential to the life of the adult being, 

 45% of the insects that survived the winter living until the last of 

 May, 20% until the middle of June, 10% until the first of July and 3% 

 until the first of August, although in captivity and fed only on fresh 

 plum and fresh peach leaves. While they always showed a strong 

 preference for plum and peach leaves, they also ate apple leaves, celery, 

 cabbage and bits of Irish potato vines. Quince, willow and rose vine 

 leaves were eaten sparingly. Attempts were made to eat the pear leaf, 

 but the epidermis seemed to be too tough. The leaves of the maple, 

 black and v.'hite mulberry, haw, wild and cultivated cherry, wild plum, 

 raspberry, grape vine and honeysuckle were not touched. Fresh slices 

 from winter apples and also dried peaches were readily eaten, and dried 

 peach and cultivated plum leaves after having been moistened in 

 water. 



For a single, apparently thoroughly satisfying meal a curculio was ob- 

 served to cut a hole 1.5x4.5 mm. in size in a fresh, green plum leaf in 

 two and one-half hours. The action of the snout, as seen under a hand- 

 glass, was similar to that of the head of a sheep or a cow while grazing. 

 The accompanying halftone (Fig. 1) shows the peach leaves eaten by 

 18 curculio from September 20 to 26, 1909, while in captivity in a 

 Mason jar. The companion halftone (Fig. 2) shows the control leaves 

 which were in an adjoining jar. 



During the winter a number of curculio were kept in jars covered 

 with tarlatan, near a window in the celler, where the temperature 

 was never below 50° F. They continuously fed on moistened dried 

 peach and plum leaves and slices from fresh winter apples and bits from 

 dried peaches, though not with the avidity as in the case of the 

 fresh leaves of the spring and summer. 



The ability to stand cold was evidenced by the following experiment: 

 A tin can, five inches in diameter and eight inches deep, capped with 

 fine copper wire mesh, was filled to five inches with earth and sunk five 

 inches in the ground in the back yard, numerous fine holes having been 

 punched in the sides and bottom to admit moisture and to prevent 

 the entrance of ants. In this can twenty-five curculio were placed 

 November 1st, 1908, together with a handful of dried plum leaves and 

 several slices of dried peaches. On the 7th of the following March, 

 which was a bright warm spring day, ten of the curculio were found 

 alive among the leaves. These were removed from the can. On the 



