250 



looking as though they had been swept by fire; hence the name 

 "fire-bug." The Hfe-history and habits of this pest, its food-plants 

 and methods of control are "discussed. [R.A.E., A, vi, 300 ; vii, 243.] 

 It is urged that every effort should be made to prevent it from 

 spreading fiirther northward, and the importance of destroying the 

 first generation of bugs, i.e., Ihose that have hibernated through the 

 winter, and their progeny is emphasised. The co-operation of growers 

 is absolutely essential if success is to be attained. 



Back (E. A.). Book Lice or Psocids. — U.S. Depf. Agric, Washington, 

 B.C., Farmers' Bull. 1104, February 1920, 4 pp., 1 tig. 



The habits of Psocids (book lice) and the conditions favourable to 

 their increase are described. They are most numerous in houses 

 during late summer and early autumn, and are most abundant in 

 damp, shaded rooms not in general use, and m houses that have been 

 shut up for long periods. When a few individuals are present, which 

 is frequently the case, as they easily enter a house from outside, 

 thoroughly airing a room after heating to 120° to 140° F. for several 

 hours and moving the furniture into the sunshine should be sufficient 

 to rid it of them. When the numbers become alarming in any room 

 the breeding-place should be at once located. If the source is a 

 mattress, as is often the case, this should be burnt and the room 

 fumigated with sulphur, using 1 lb. for every 1,000 cubic feet of space. 

 Chests, boxes, trunks, etc., can be fumigated satisfactorily with 

 carbon bisulphide. 



Kalkus (J. W.). Orchard Horse Disease. — Amer. Jl. Vet. Med., 

 Chicago, xv, no. 4, April 1920, pp. J 39-143, 8 figs. 



Present knowledge of this disease indicates that it is confined to 

 the irrigated apple orchard districts where lead arsenate sprays are 

 commonly used. The disease may possibly l)e due to poisoning of 

 the lucerne or hay crop under the fruit trees owing to excess of the 

 spray. Doubt is thrown on this theory by the fact that the 

 symptoms of the disease do not resemble arsenic or lead poisoning 

 in every particular. If the theory is correct, the chronic form of 

 the disease may be due to the lead, and the acute form to arsenical 

 poisoning. It is hoped that a definite conclusion may be reached as 

 a result of the experiments now being conducted at the Washington 

 Agricultural Experiment Station. 



Paillot (A.). La Phagocytose chez les Insectes.— C. K. Soc. Biol,, 

 Paris, Ixxxiii, no. 12, 27th March 1920, pp. 425-426. 



Eeferring to Metalnikofi's recent paper on immunity in insects 

 [R.A.E., A, viii, 163], the author points out that it is in general the 

 saprophytic microbes that are pathogenic to the larvae of Galleria 

 mellonetla, while those that are highly pathogenic to man or the 

 larger vertebrates are less pathogenic to them, and sometimes 

 incapable of causing their death. In many previous papers, the 

 author has expressed the opinion that phagocytosis is not the only 

 method of defence of larvae inoculated with entomophytous microbes ; 



