INJURIOUS TO MINOR VEGETABLE CROPS 259 



dusted with a whitish powder and bears tufts of white waxen 

 threads. The insects often occur in dense masses on the roots 

 and may retard the growth of the plant. They are attended 

 by ants and are probably carried by them to new feeding 

 grounds. The life history of this species is very imperfectly 

 known and its wild food plants have not been determined. 



The lettuce root-louse rarely causes enough injury to warrant 

 repressive measures. 



Reference 

 Fitch, 14th Kept. State Ent. N. Y., pp. 360-363. 1870. 



Other lettuce insects 



Cabbage loo per : 8 



Garden web worm : 18 



Turnip aphis : 27 



False chinch-bug : 47 



Celery looper : 191 



Spinach aphis : 105 



Western twelve-spotted cucumber beetle: 114 



Belted cucumber beetle : 115 



Garden springtail : 139 



Bean thrips : 69 



Garden flea-hopper : 77 



Dark-sided cutworm : 268 



Striped cutworm : 270 



Variegated cutworm : 276 



Glassy cutworm : 279 



Yellow-headed cutworm : 281 



Spotted-legged cutworm : 282 



Clover cutworm : 284 



Pale-striped flea-beetle : 321 



Root-knot nematode : 338 



Millipedes: 342 



Slugs: 354 



