393 



Zetek (J.)- Hawaiian Sugar Cane Borer in Costa Rica : A Correction. 



—Jl. Econ. Entom., Concord, N.H.. xiii, no. 3, June 1920, p. 323. 



The author corrects a statement made in a previous paper [R.A.E., 

 A, vii, 395] reporting the occurrence of Rhabdocnemis obscura in Costa 

 Eica. This should have been the banana root borer, Cosmopolites 

 sordidus, Germ. 



Pettit (R. H.). Tree Hoppers and Alfalfa. — Jl. Econ. Entom., Con- 

 cord, N.H., xiii, no. 3, June 1920, p. 323. 



A tree-hopper, presumably Ceresa buhalus, has been found to cause 

 considerable damage in young orchards in Michigan, the injury 

 occurring in the autumn when eggs are laid on young apple-trees 

 in their first or second year. This damage has been found to occur in 

 practically all cases in orchards planted with lucerne, while adjoining 

 orchards free from lucerne have shown little or no injury. 



Herbert (F. B.). Cypress Bark Scale, Ehrhornia cwpressi, Ehrh.— 

 U.S. Dept. Agric, Washington, D.C., Bull. 838, 5th June 1920, 

 22 pp., 6 plates, 5 figs. 



Ehrhornia cupressi, Ehrh. (cypress baric scale) infests a large propor- 

 tion of the Monterey cypress trees {Cupressus macrocarpa, Hartw.), 

 which are among the most popular shade and ornamental trees in 

 California. Originally a pest of incense cedar {Libocedrus decurrens), 

 it has spread through large areas by the usual agencies of wind, birds, 

 etc., and by the transportation of infested nursery stock. A map 

 shows its present distribution on both plants. The presence of the 

 scale is indicated by a secretion of white cottony wax ])rotruding 

 from the bark crevices, and covering the twigs, and imder each scale 

 may be found a small brown ring in the cambium showing where the 

 tissue has been killed. On one or two limbs of an infested tree tlie 

 foliage tmns yellow, then red or brown, and this spreads until the 

 entire tree is killed. Other food-plants include Arizona cypress 

 {C. arizonica), Guadalupe cypress {G. guadaliipensis) and occasionally 

 deodar (Cedrus deodara). 



A description of the various stages is given. There is only one 

 generation in a year, the limits of which are not very well defined. 

 The males appear in autumn, and are most abundant in October and 

 November, when most of the females have moulted for the last time 

 and are about half grown. After mating, the males rapidly die ofi. 

 The adult females hibernate, their eggs developing during the winter 

 and early spring. Oviposition begins on the first warm spring days 

 and continues throughout the summer ; in the autumn the females 

 shrivel and die, but by that time the females of the next generation 

 are well developed. The eggs hatch in from 30 to 40 minutes after 

 deposition, and the larvae wander about until they find a suitable 

 crevice in the bark where they remain and feed. First-instar larvae 

 are found from April to mid-October, those of the second instar from 

 mid-May to mid-November, and adult females all the year round. 

 (701) c 



