MISCELLANEOUS NOTES ON TRUCK-CROP INSECTS. 97 



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

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

 it has been noticed that earlier accounts of the related European 

 Phadon hetuhv L., known as the mustard beetle and " blackjack," 

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

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

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

 crops near Ely, Another account of this insect is given in the same 

 author's report for 188(5.'' 



The trater-cress sowbug. — April lO, 1007, Mr. C. A. Killinger, Ship- 

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

 IjvacJnjiD'vs 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 flout downstream. Our correspondent thought 

 that this species was brought to that section from Virginia. 



Experiments conducted with lime in a small spring the previous 

 summer succeeded in killing most of the sowbugs, but plenty of them 

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

 cress, causing it to turn yellow. 



December 23, 1008, ]\Ir. F. W. Houston, a grower and shipper of 

 water cress at Lexington, Va., wrote of this species, inquiring 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, 1000 — he sent specimens. In this connection he wrote as 

 follows : 



I have a spring under cultivation which has heen Infested by them for several 

 years. I fought them for a time by i)uttiu{; the water into ditches and exposing 

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

 ai)plications of lime; this, of course, was done during the early summer, 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 si)ring, 

 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 

 >hould be drawn or turned off and that the cress should.be completely 

 tiestroyed and the spring reset with uninfested cres.s. 



" Manual of In.iuri<ius Insects and Methods nf Tri'vention. London. ISKO, 

 pp. 1.51-156. 



* Report on Injurious Inse<ts for issc, pp. r>!»-00. 



o 



