THE RICE WATER-WEEVIL. 



NATURE OF ATTACKS BY LARV.E. 



Mr. Hood has stated that the larvae are first found in the rioe fields 

 from one to three weeks after the turning on of the water, the 



time of their inception varying 

 with the weather. Hot weather 

 accelerates their development. 

 The young larva?, which have 

 doubtless hatched from eggs laid 

 in the roots, begin to feed on 

 them, and in course of time as 

 the larva? increase in size they 

 devour or sever large portions 

 of the root system. They have 

 been known to eat holes in large 

 rice roots and burrow into them. 

 Mr. W. D. Pierce, at Beaumont, 

 Tex., in 1004, found vigorous 

 larva? consuming the entire in- 

 terior of the roots. Figure 1, 

 c, gives a representation of six 

 feeding holes made at a distance 

 not more than one-fourth of an 

 inch apart as Mr. Hood viewed 

 them. The common methods of 

 attack result in a pruning of the 

 roots, after which the severed 

 portions rot and the remaining 

 parts are further marred with 

 feeding scars. At this stage the 

 hold of the plant upon the soil 

 is greatly weakened and it can 

 be pulled from the ground with 

 ease. In some instances on rec- 

 ord the root systems were en- 

 tirely destroyed and the rice 

 plants floated in the water. 



The injuries done by the larva' 



first cause the leaves of the rice 



plants to turn a pale yellow and 



droop, the lower blades often 



resting on the water. With 



severe attacks some of the leaves may die. These effects in the fields 



become most pronounced on plants growing in depressions and low 



portions of the land into which the water first flowed and where it 



Fig. 2. — Lamp-chimney cage for rearing 

 and observing the rice water-weevil : a, 

 Glass lamp chimney ; b, vessel containing 

 plaster of Paris : c. glass tube ; d, wire 

 support ; c, rice plant ; /, string lift ; g, 

 gauze ; h, rubber band ; i, j, beetles feed- 

 ing. (Original.) 



