106 



Boston. The fact of its not having occurred in earlier collections 

 points to its limited distribution, while the size of the colonies proves 

 that they must have been established for some years, having probably 

 been accidentall}'' introduced from Europe. In the case of 

 R. fiavijpes the development to the adult state apparently takes place 

 as early in the spring as the weather will permit, that of R. lucifugus 

 occurring about 3 weeks later. 



YoTHERS (W. W.). Spraying for the Control of Insects and Mites 

 attacking Citrus Trees in Florida. — U.S. DepL, Agric, Washingto^i, 

 D.C., Farmers' Bull no. 933, March 1918, 38 pp., 24 figs. 

 [Keceived 3rd January 1919.] 



The bulk of the subject matter of this bulletin has already been 

 noticed [see this Review, Ser. A, i, p. 186, iii, p. 444, and vi, p. 216]. 



Watson (J. R.). The California Delphasius. — Florida Buggist, 

 Gainesville, ii, no, 2, September 1918, p. 88. [Received 3rd 

 January 1919.] 



Delphastus catalinae, a Coccinellid predaceous on whiteflies, is 

 multiplying most satisfactorily in Florida and arrangements have been 

 made for distributing it further. 



Watson (J. K.). An Outbreak of the Cotton Stainer on Citrus. 



— Florida Buggist, Gainesville, ii, no. 2, September 1918, pp. 

 88-90. [Received 3rd January 1919.] 



A cotton stainer, Dysdercus suturellus, H.S., has been causing loss 

 to citrus and avocado growers in the southern parts of Florida by 

 puncturing the rind of the fruit and causing it to drop from the tree 

 and decay. The punctm'es are smaller than those caused by Nezara 

 viridula (pumpkin bug), being entirely invisible to the naked eye. 

 The insects, which feed by day on thin-skinned varieties of citrus, 

 chiefly tangerines, are distinctly gregarious, collecting in colonies 

 on the leaves and fruit both on the tree and on the ground. 



No outbreak has been recorded in communities where no cotton 

 has been planted, whereas groves near cotton have been found heavily 

 infested with both young and adults, and even those three-quarters of 

 a mile distant with the strong-flying adults. 



If the pest is to be controlled, it is essential that cotton should 

 not be planted in citrus areas, while fowls afford an accessory 

 means of keeping it in check. A closely-related species, D. delauneyi, 

 Leth., has been effectively dealt with in St. Vincent by the destruction 

 of its wild food-plants, and it is thought that the same result might 

 be obtained in Florida by destroying the Spanish cockle-burr {Urena 

 lobata), on which it largely breeds in the absence of cotton. 



VoGLiNo (P.), Osservazioni suUa Biologia delle Tignole della Vite 

 e sulle Esperienze di Lotta fatte nel 1915-1916. [Observations 

 on the Biology of the Vine Moths and on Control Erperiments 

 made in 1915-1916.] — Separate from Boll. Minist. Agric, 

 Indusiria e Commercio, Serie B, Rotne, July-October 1917, 7 pp. 

 [Received 2nd December 1918.] 



As regards the spring generation of Polychrosis hotrana and Clysia 

 ambiguella in Piedmont in years in which the spring has a succession 



