434 JOURNAL OF ECONOMIC ENTOMOLOGY [Vol. 7 



^^ surface of dirt to one 



^^^^^ ^ y of the principal roots. 



"~- =-^^:^^^^^ ^^^-^ <^-'^^'-^ '^ ^■r==-^-= W\ Here she inserts the 



"^ ==—=-= - jy ^y merely forcing 



Fig. 24 — Egg of Rice Water Weevil in section of rice root, the tip of this organ 



The egg has been exposed by removing the epidermis of through the epider- 



theroot. Enlarged (original) mis of the root. The 



egg (fig. 24) is then 

 placed longitudinally just inside the epidermis. The egg is cylindrical, 

 pearly white, and about one thirty-second of an inch in length. It is 

 three or four times as long as broad and is barely visible to the naked 

 eye. The writer, with the aid of a binocular microscope has found 

 as many as three eggs laid end to end, apparently through the same 

 hole in the epidermis. In other cases only one in a place was found. 

 The microscope failed to reveal any evidence of the use of the 

 mandibles in making the hole in the epidermis for the insertion of the 

 ovipositor. 



For the first few days of its existence the larva remains within the 

 root in which it was hatched, feeding upon the inner root tissues and 

 increasing in size. It advances along the root longitudinally, eating 

 out a passageway as it goes. By the time it has exhausted the nutri- 

 tive qualities of this first root, it is large enough to proceed farther and 

 goes to another root undeterred by the surrounding mud. Whether 

 it feeds Httle or much upon successive roots, practically all roots 

 attacked are killed. Often several larvae are found among the roots 

 of a single plant (pi. 13) and work great destruction there. At this 

 stage many of the larvae are easily disclosed by pulling up infested rice 

 plants and shaking the roots in water until washed clean of mud. 

 Some larvae always float on the surface of the water, while others sink 

 to the bottom. When the roots of a rice plant are severely injured 

 the leaves turn yellow, and according to Tucker ^ may even fall over 

 upon the surface of the water. 



When fuUgrown, the larva is from one-fourth to one-half inch in 

 length, very slender, and milk white. In preparation for the coming 

 change, the larva gathers about itself an egg-shaped mass of dirt which 

 it attaches to one of the healthy rice roots (pi. 13). The outside of this 

 pupal cell is uniformly even and oval in shape. It would be interesting 

 to know just how the larva accomplishes this result, but in the nature 

 of things observations along this line were impossible. Within the 

 pupal cell is a space from which water is excluded. Safe within this 



1 Bureau of Entomology Circ. No. 152, p. 8 (footnote). 



