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Chittenden (F. H.) & Marsh (H. O.). The Beet Leaf-beetle.— 

 U.S. Dept. Agnc, Washington. D.C.. Bull. 892, 25th October 

 1920, 24 pp., 4'figs., 9 plates. [Received 22nd February 1921.] 



In the Rocky Mountain States sugar-beets are attacked by the 

 adults, and especially by the larvae, of the beet leaf-beetle, Monoxia 

 pundicollis. Say. Prior to 1897 this Chrysomelid had confined its 

 attack to weeds or wild plants. A description of the various stages is 

 given. M. puncticollis occurs along the Atlantic sea-board of the 

 United States, in California, and in the alkaline regions of Colorado, 

 Utah, and New Mexico. The favourite food-plants of the adults and 

 larvae are Chenopodium album (lamb's quarters), Dondia spp. (sea- 

 blite) and sugar-beet. The hibernating beetles appear in March and 

 April, and soon begin ovipositing on the under-side of the leaves. The 

 larvae eat holes in the leaves, and when mature burrow into the ground 

 to a depth of a half to two inches and form cells in which the pupae 

 develop in eight to nine days. Two generations and a partial third 

 occur annually in the Arkansas Valley of Colorado. 



The adult beetles hibernate in alkali areas under tufts of grass, 

 heaps of dead weeds, and other rubbish, and their destruction in their 

 winter quarters has proved an effective and practical method of control. 

 The dead grass and weeds should be burned between mid-November 

 and 1st March, and it is necessary that the work should be thoroughly 

 done. Traps, consisting of heaps of weeds or bundles of straw or hay, 

 may be placed, not later than August, so that they may become well 

 settled before the beetles seek them for winter quarters. Fowls in 

 infested fields will also destroy many of the beetles. 



The use of arsenicals has not been entirely successful, and is not 

 needed in view of the excellent results obtained by destroying the 

 hibernating pests. 



Natural enemies are numerous, and include the Coccinellids, Hippo 

 damia convergens, Guer., H. sinuata, Muls., and H. glacialis, F., 

 which feed on the eggs and young larvae of the hibernated beetles 

 until Aphids become abundant. The nymphs of the Pentatomid 

 bug, Perillus biocidatus, F., var. claudius. Say, feed on the larvae, and 

 the adult bugs on the beetles. One species of internal parasite, a 

 Tachinid, Hypostena sp., was reared. This fly is rare. Toads, poultry 

 and wild birds, and a fungous disease are among the other natural 

 checks. 



Chittenden (F. H.) & Marsh (H. O.). The Western Cabbage 

 Flea-beetle.— 17.5. Dept. Agric. Washington, D.C., Bull. 902, 

 22nd October 1920, 21 pp., 4 figs., 1 plate. [Received 22nd 

 February 1921.] 



The western cabbage flea-beetle, Phyllotreta pusilla, Horn, is a 

 most troublesome pest of cabbage, turnips and other cruciferous crops, 

 sugar-beets, other vegetables, and garden plants in the western 

 States. The injury is chiefly due to the attacks of the over-wintered 

 adults during June and July, but more or less injury is done during 

 the growing season. Minute, pit-like holes are eaten in the leaves of 

 young plants, the lower surface being usually selected. Considerable 

 haun is often done to seed-beds. The damage caused by the larvae 

 is negligible. 



The entire life-cycle from egg to adult rmy be passed in about 

 30 days in June and July, and there are at least three annual genera- 

 tions. In its more northern range P. pusilla hibernates under clods, 



(2758) p2 



