56 JOURNAL OF ECONOMIC ENTOMOLOGY [Vol. 6 



Habits of the Adults. Upon undertaking field investigations 

 in the spring of 1909, I visited various rice-growing localities in search 

 of the insects, but did not find adults in sufficient numbers for satis- 

 factory observation until June 3, on which date I visited a plantation 

 three miles north of Lake Arthur, La. Here I found the adults very- 

 abundant in a field of Japan rice about eight inches in height. The 

 irrigating water had been admitted to this field for the first time on 

 June 1, just two days before my arrival and it had not yet reached the 

 higher portions of the field. Here was an average of at least one weevil 

 to every five or six rice plants, but none were found in rice which the 

 water had not yet reached and no larvse to speak of could be found on 

 the roots of older rice. Some of the adults were swimming about, 

 others were mating and the majority were feeding on the rice leaves. 



The weevils are rather sluggish when out of the water, crawling 

 slowly about the leaves "of the rice. They can be picked up readily 

 in one's fingers and frequently when touched they will play possum, 

 or ''sull," and fall off into the water where they either swim away or 

 continue to ''sull" and float on the surface. They cannot be made to 

 take flight, even by throwing them into the air. They swim with 

 great facility and considerable speed, either on the surface of the 

 water or below it, and they apparently find swimming a more con- 

 venient means of traveling from one rice plant to another than flying. 

 That they do fly, however, with ease, is shown by their night flights 

 to brilliant lights and doubtless their principal, or sole, means of dis- 

 semination from field to field is also by flight. 



Feeding Habits. Both the males and females feed upon the rice 

 in an interesting way. The weevil takes a position on the upper 

 surface of the leaf with body parallel to its main axis. The mandibles 

 tear up the epidermis and the operation is assisted by the beak, which 

 is used to push and lift, much as a hog uses its nose for rooting. As 

 feeding progresses the weevil moves forward, feeding, usually, towards 

 the apex of the leaf and makes a feeding scar about as wide as the 

 spread of the mandibles and from 1-16 of an inch to two or more 

 inches in length, depending on the length of time the individual is 

 engaged in feeding. The mandibles do not pierce through the leaf 

 but remove only the epidermis, "skeletonizing" the leaf at the point 

 of feeding. As the leaf grows, or is whipped about by the wind, the 

 skeletonized portion breaks through, making an oval or long slit in 

 the rice blade. 



It seems to make no difference, on a reasonably warm day, whether 

 the weevils feed in the sun or in the shade, they being found feeding 

 indiscriminately in both situations. When the day is extremely hot 

 and the sun bright, the weevils show some disposition to avoid the 



