ENTOMOLOGY. 4P>5 



agitated the while. The amount of terebeiithin used is an important 



matter. It* less than 2 per cent be used, it will be ineffective; if too 

 much is used it will injure the grapes. Numerous complaints against 

 the " pyrale " ( (Enophtira pilleriana) are also noted. The best method 

 of destroying both these insects is thought to be by means of hot water. 

 The destruction of the "Sauva," F. W. Dafert and L. Eivinus 

 [Belai.Inst. Agron. Sao. Paulo [Brazil], 7-8(1896), pp. 221-267, figs. 12, 

 tables 2). — The means of destroying the ant Atta sextens, which is a 

 very serious pest in Brazil, are somewhat exhaustively considered. Its 

 habits and its intelligence render it a difficult insect to combat. 

 Its mines extend to considerable depths and over an area as much as 

 100 meters broad, while the individuals number into the millions. The 

 various methods of combating the insect are brought together and 

 classified as (1) those in which poisonous gases, sulphurous fumes, etc., 

 are used; (2) destroying by the explosion of gases (bisulphid of carbon 

 or benzine vapor); (3) burning out with illuminating gases; (4) smok- 

 ing out; and (5) mechanical measures. Various pieces of apparatus 

 to be used in the work are figured. The most noteworthy facts regard- 

 ing the insect are: 



(1) The ants' resistance to destruction by poisons is remarkable. 

 They will withstand a 2£-hour exposure in vacuum and will live for a 

 day while under pressure. 



(2) They are readily destroyed by explosions, if in contact with the 

 exploding medium. They can not withstand a temperature above 50° C. 



(3) The most practical means of destroying them is by burning out 

 the nests by using carbon bisulphid which, after it has saturated the 

 nest, is to be exploded; by the use of burning sulphur and vapors of 

 arsenic. 



(4) The nests must be attacked on all sides. 



The destruction of small insectivorous birds should be avoided. The 

 tables given bring out the changes that colonies studied underwent as 

 well as the applicability of the various destructive measures. 



The destruction of insects injurious to the vine, P. Coste- 

 Floret [Prog. Ayr. et Tit., 28 (1897), Nos. 29, pp. 64-72; 30, pp. 94-102; 

 32, pp. 151-161; 33, pp. 178-181, figs. 22).— This essay treats the subject 

 according to the 4 seasons of the year. Some of the well-known reme- 

 dies are noted. The common French remedy (hot water) against the 

 larva? of the "pyrale" ( (Enophtira pilleriana) is discussed at some length, 

 and a heating apparatus mounted on wheels is figured. The expense 

 of this remedy is computed at 53.5 francs per hectare (about $4.12 per 

 acre). With this is compared the sulphur-fume method or " clochage" 

 which costs from 33.3 francs to 40.8 francs per hectare (about $2.56 

 to $3.14 per acre), according as slow matches or ordinary sulphur is 

 used. Where slow matches are used, 36 kg. per acre are necessary, 

 as contrasted with 44 kg. when ordinary sulphur is used. Other 

 methods noted are the use of acid sprays, carbon bisulphid, an 



