343 



La Formica argentina. [The Argentine Ant.] — R. Lab. Ent. Agrar., R. 



Scuola Slip. Agric, Poi'tid, Circ. 1 [1920], 6 pp., 1 fig. [Received 



11th May 1921.] 

 This circular has been issued in view of the threatened introduction 

 from France into Italy of Iridomyrmex humilis, Mayr (Argentine ant). 

 Brief notes on this pest, its distribution and habits, are given. Attention 

 is drawn to the need for a careful examination of food-stuffs, fruits and 

 plants in railway trucks and in ships. Remedial measures include 

 poison-baits, for which the formula now adopted in the United States 

 is given. 



SiLVESTRi (F.). II CrisomJalo o Cocciniglia rossa degli Agruini 



[Chrysomphalits didyospermi, or the Red Scale of Citrus.'] — 

 R. Lab. Ent. Agrar., R. Scuola Sup. Agric, Portia, Circ. 2, 10th 

 March 1921, 11 pp., 14 figs. [Received 11th May 1921.] 



Citrus plants in south Italy and Sicily are infested by the following 

 scales ■.^Lepidosaphes pinnaeformis, Parlatoria zizyphi, Aspidiotus 

 hederae, Saissetia oleae, Pseudococcus citri, Icerya purchasi, Coccus 

 hesperidmn, Ceroplastes sinensis, Aonidiella citri, and Chrysomphalus 

 dictyospermi. The last-named has greatl}' increased in recent years in 

 the provinces of Naples and Caserta, and for this reason special atten- 

 tion is drawn to it. The natural enemies of this scale in Italy are 

 Aphelinus, Chilocorus, Exochomus and Rhizobius. In Sicily and Italy 

 infestation is often very greatly reduced by a mortality due to an un- 

 known cause. As natural checks are unreliable, artificial measures must 

 be employed ; until hydrocyanic acid gas is available for fumigation, 

 calcium polysulphide is the insecticide recommended. The materials 

 required are fresh, well-burnt quicklime containing not more than 10 

 per cent, of impurities ; very finely-powdered sulphur of 99-100 per 

 cent, purity ; and containers of tin, iron or earthenware, or wooden tubs 

 if the quantity of solution is large. The formula is as follows : Stone 

 quicklime, 1 lb.; sulphur passed through a sieve, 2 lb ; water, 1 -3 gals. 

 About one-third of the water is slightly warmed, the lime is then added,- 

 and when slaking begins the sulphur also. After mixing, the remainder 

 of the water is poured in, mixing is continued and the solution is then 

 boiled for forty-five minutes to an hour. From 4 to 8 parts of this stock 

 solution is added to 100 parts of water to form the actual spray solution ; 

 it is not feasible to use a constant amount of 5 parts, because the density 

 of the stock solution varies and allowance has to be made in accordance 

 with the reading obtained from a polysulphide meter, such as Martelli's. 

 Greater adhesiveness is obtained by adding 4 per cent, of flour paste 

 to the final spray solution ; the paste is made with 1 part by weight 

 of flour and 8 parts water, and it must be boiled, water being added to 

 make up loss through evaporation. Tlie sprayers should not have 

 copper parts. The spray must be thoroughly applied when m.ost of 

 the larvae have hatched, provided the trees are not in full blossom. 

 A second application must be made 15 or 20 days later. 



Grandi (G.). Di alcuni Afidi comunemente dannosi aU'Agricoltura. 



[Some Aphids ordinarily injurious to Agriculture.] — R. Lab. 



Ent. Agrar., R. Scuola Sup. Agric, Portici, Circ. 3, 15th March 



1921. 22 pp., 10 figs. [Received 11th May 1921.] 



A short, general description is given of the various forms of Aphids, 



with notes on their morphologv, biology and natural enemies. The 



latter include fungi, especially Entomophthoraceae, predatory Diptera, 



