476 



The different stages are described and compared. Tlie eggs are laid 

 singly on the bark during June and July. As soon as they are hatched 

 the young larvae bore into the bark and mine down to the wood, where 

 they tunnel backwards and forwards through the outer wood and inner 

 bark until they are full grown. The pupal cell is formed in the outer 

 w^ocd or bark. Observations indicate that in California both species 

 pass the vnnter as prepupal larvae in the cells. Some individuals pass 

 through two winters in this stage. The pupal stage lasts from 2 to 8 

 weeks according to climatic conditions, and the adults remain in the 

 pupal cell from one to several weeks. Young beetles of C. femorafa 

 have been found in the cells from 28th March to 9th August, those of 

 C. maU from 16th April to 7th August. In the field the beetles have 

 been taken from 15th May to Uth August and 24th April to 7th August 

 respectively. 



The remedial measures advocated include the cutting away of the 

 dead bark and covering the wound, after killing the borer, wnth a 

 dressing of coal-tar or liquid asphalt. Any kind of protection that 

 keeps the sun from the exposed bark is also desirable. 



Ferris (G. F.). Lac-producing Insects in the United States (Hemiptera,. 

 Coccidae). — Jl. Econ. Entom., Concord, N.H., xii, no. 4, August 

 1919, pp. 330-333. 



It having been thought that a lac insect, Tachardia larreae, Comst.,. 

 occurred in sufficient abundance in the south-western parts of th& 

 United States on the creosote bush {CoviUea glutinosa) to make the- 

 commercial recovery of the lac possible, investigations on the point 

 were undertaken and are here described. The results show^ that lac 

 cultivation under natural conditions cannot be adopted as a successful 

 commercial enterprise. Artificial propagation of the insect has not 

 been tried, as the expense would be great and would probably only- 

 yield negative results. 



Herbert (F. B.). Insect Problems of Western Shade Trees. — Jl:. 

 Econ. Entom., Concord, N.H., xii, no. 4, August 1919, pp. 333-337. 



The necessity for controlling shade-tree pests from the point of view 

 of the value of these plants as well as the probability of their spread to- 

 fruit trees is discussed. Remedial measures suggested include planting 

 the trees further apart to allow the sun to penetrate and the use of 

 Dower- sprays. 



The most important shade- tree pests include : — Gossyparia spuria, L.. 

 (European elm scale) ; Ehrhornia cupressi, Ehrh. (cypress bark scale) ; 

 Saisseiia oleae, Bern, (black scale) ; Pseudococcus citri, Risso (citrus 

 mealy bug); P. longispinns, Targ. (long-tailed mealy bug); 

 P. maritimus, Ehrh. {bakeri, Essig) ; P. gahatii, Green {citrophilus, 

 Claussen) ; P. aurilanatus, Mask, (golden mealy bug), which is especially 

 harmful to Araucaria bidwilli, A. excelsa and A. imbricata ; Stomacoccus. 

 platani, Ferris (sycamore scale) ; Phjsolermes insignicola, Craw^ 

 (Monterey pine scale) ; Toumeyclla sp. ; Aspidiotus pini, Comst.. 

 {californicus, Coleman) (California pine-leaf scale) ; Icerya purchasi,. 

 Mask, (cottony cushion scale), which causes particular damage tc\ 



