434 



WiLDERMUTH (V. L.)- The Desert Corn Flea-Beetle. — U.S. Dept. 

 Agric, Washington, D.C., Bull. no. 436, 7th February 1917, 23 pp.. 

 1 plate, 7 figs. [Received 17th July 1917.] 



Chaetocnema ectypa, Horn, occurs in the semi-arid areas of the 

 south-western United States, where it attacks maize, sugar-cane, 

 Sudan grass, wheat, barley and lucerne, its natural food-plants being 

 apparently some of the native grasses. The larvae attack the plants 

 below the ground, while the adults feed upon the leaves. The eggs are 

 deposited at or near the surface of the ground and hatch in about 

 six days. The larval stage lasts on an average 32 days, the larvae 

 when mature pupating in the soil beside the roots. The length of the 

 pupal stage is very variable, the total length of the life-cycle being 

 about seven weeks. There are three or four generations in each year. 

 Adults hibernate under rubbish, or about the base of grasses. 

 Predaceous enemies include the nymphs and adults of the Hemipteron, 

 Reduviolus ferns, L., which attack the adults ; mites {Pediculoides sp.) 

 have frequently been found on the beetles ; the larvae and prepupae 

 are preyed upon by a small Bethylid wasp, Neurepyris sp. The 

 number of adult flea-beetles can be greatly reduced by cleaning up 

 hibernation quarters and eradicating some of the weed host- plants, 

 such as Johnson grass, salt grass and Bermuda grass. In moist soil 

 the larvae pupate near the surface of the ground and within a few inches 

 of the plant ; careful cultivation after each irrigation will therefore 

 destroy many pupae. Small areas can be treated successfully with a 

 spray of 2 lb. arsenate of lead in 50 U.S. gals, water with strong soap 

 in solution. This is both a repellent and a poison. 



Hhpkins (A. D.) & Snyder (T. E.). Powder-Post Damage by Lyctus 

 Beetles to Seasoned Hardwood. — U.S. Dept. Agric, Washington, 

 B.C., Farmers' Bull. no. 778, January 1917, 20 pp., 13 'figs. 

 [Received 17th July 1917.] 



Seasoned hardwood in North America is very liable to attack by 

 Lyctvs beetles, whose presence can be detected by the fine flour-like 

 powder found on or beneath stored piles of hardwood products. When 

 the wood is split open the interior is found to consist of a mass of 

 closely-packed, powdery material, which has been held together by a 

 thin outer shell of sound wood, in which the emergence holes of the 

 adults can be seen. The white or sap-wood only is damaged, the 

 beetles never attack the heart- wood. Varieties especially hable to 

 this injury are hickory, ash and oak ; other species less frequently 

 attacked are persimmon, osage orange, black walnut, butternut, 

 maple, elm, wild cherry, locust, poplar, sycamore, eucalyptus, 

 sassafras, orange wood, fig and bamboo. 



The species of Lyctus dealt with in this bulletin are : L. planicollis, 

 Lee, of which the life-history and habits have previously been 

 described [see this Review, Ser. A, iv, p. 324] ; L. linearis, Goeze, 

 which in life-history and habits closely resembles L. planicollis ; 

 L. parallelopipedus, Melsh., which attacks commercial products made 

 from persimmon, hickory, ash, oak and bamboo, and also lives in the 

 dead wood of osage orange, sassafras and fig ; adults are active from 

 mid-March to the end of August, general emergence being in June and 

 July ; and L. cavicollis, Lee, which is recorded from California in 



