TKOCIEDINGS OF THE THIRD ENTOMOLOGICAL MEETING 559 



from increasing unduly. Besides cotton, I have seen the tubes with 

 adults on Hibiscus panel urifonnis at Pusa when the crop was being 

 tried as a fibre crop. The tubes as well as the habits of the nymphs 

 correspond with those found on Zizyphus jvjuba. In particular years 

 and on some varieties of cotton this pest is really very serious and does 

 more damage than either Sylepla derogata or other leaf-eating cater- 

 pillars put together. During 1912, a complete cycle was found to last 

 for 40-41 days thu ; : — 



Eggs laid 21st April 1912. 



Eggs hatched .... 28th April 1912. 



Adults emerged . . . 31st May 1912 to 1st June 19?2— 40-41 



days. 



Next to the three mealy-bugs, P. hirsutus, P. corymbatits and P. 

 virgatus, and Machwrota planitiw, the cotton Eriophyes (probably 

 Eriophyes gossypii ?) has been found in certain years to retard the 

 growth of the plants considerably. Prior to 1914, stray specimens 

 were found on the leaves of certain varieties of plants. But in 1915 

 and again in 1916 the pest was found to have extended its range and 

 to be more or less present on all the short-leaved varieties of cotton. 

 At first it appears as a small whitish spot on the leaves, which increases 

 with the subsequent curhng of the leaves. It has been found bad on 

 certain varieties of cotton, especially those obtained from the Bombay 

 Presidency. As varieties of cotton from the United Provinces such 

 as Aligarh white and Aligarh yellow were sown close to those of Bombay, 

 these in turn again became heavily infested and in consequence some of 

 the worst infested plants had to be removed fi-om time to time and 

 burned. At first if the tiny silvery or brownish spots are examined 

 under the microscope, the adults will be seen as tiny little whitish mites 

 with body distinctly transversely ringed moving freely about the proli- 

 feration of the leaf-tissues caused by them. Soon after the whitish 

 patch extends tmtil a greater portion of the leaf-surface becomes affected. 

 The leaf then becomes hard and crisp and the adult mites move 

 on to fresh leaves leaving behind them a few adults in their old tene- 

 ments to extend the colonies. The eggs are whitish, ovoid, and very 

 large for the size of the mite. When several leaves are affected, 

 especially the top leaves, they become hard and compact. The plant 

 is considerably thrown' back in growth and is not able to recoup its 

 lost vitality. If an infestei cotton leaf be examined under a high 

 power under the microscope, innumerable tiny whitish elongate cyUn- 

 drical bodies will be seen either moving about freely or lying either 

 upright or at an angle against the plane of the leaf. The mites 

 were found to congregate on the leaves on the top shoots which 



VOL. II rr 



