MISCELLANEOUS NOTES ON TRUCK-CROP INSECTS. 97 



Since the publication of the writer's preliminary articles on the 

 water-cress leaf-beetle and sowbiig in the present bulletin (pp. 11-20) 

 it has been noticed that earlier accounts of the related European 

 Phddon Jx'tubc L., known as the mustard beetle and " blackjack," 

 Avere made by Miss E. A. Ormerod, who furnished several references 

 with illustrations in her mainial." From this account it appears that 

 injury was first noticed, at least in England, in 1854, to white nnistard 

 cro])s near Ely. Another account of this insect is given in the same 

 author's report for 188().'' 



The iroter-cre.ss .sowhiff/. — April 16, 1907, Mr. C. A. Killinger. Ship- 

 pensburg. Pa., sent specimens of the water-cress sowbug {MancdseJliis 

 hracliijurus Harg.) in different stages, stating that it was destroying 

 his water cress, working on the leaves under water, cutting them close 

 to the stem. If the cress is light or does not grow fast, as happens in 

 winter, they also work on the stems and roots, cutting the plants loose 

 and causing them to float downstream. Our correspondent thought 

 that this species was brought to that section from Virginia. 



Exj^eriments conducted with lime in a small spring the previous 

 summer succeeded in killing most of the sowbugs, but plent}" of them 

 remained at the time of writing. The lime, however, burned the 

 cress, causing it to turn yellow. 



December 23, 1908, Mr. F. W. Houston, a grower and shipper of 

 water cress at Lexington, Va., wrote of this species, incjuiring for 

 literature and a remed3\ He stated that he had a spring under culti- 

 vation that was infested with the water-cress sowbug, and later — 

 March 11, 1909 — he sent specimens. In this connection he wrote as 

 follows : 



I have n sprliifr uiifler cultivation which has been infested by them for several 

 years. I fousht them for a time by puttinj; the water into ditches and exposing: 

 the rest of the cress bed to the sun. In these ditches I would make frequent 

 applications of lime; this, of course, was done durinj;; the early siunmer, after 

 the shipping? season closes. It seems to kill all of the sowbugs, but when I put 

 the water into the beds and reset the cress, hauling it from an uninfested spring, 

 it was not long until the " bugs " were again noticed, and in a short time they 

 were as thick as ever. 



Mr. Houston was advised that in the case of the old beds the water 

 should be drawn or turned off and that the cress should be completely 

 destroyed and the spring reset with uninfested cress. 



" Manual of Injurious Insects and Methods of Prevention. London, lSiH>. 

 pp. 1,^)1 -150. 



''Report on Injurious Insects for ISSO, pit. 59-00. 



