440 



appeared at the beginning of September and were present until the 

 middle of November, the period of maximum activity lasting from the 

 third week in September until the end of October. The insects were 

 not affected by bright sunlight, and differed in this respect from the 

 rice Fulgorids, Sogata distincta, Dist., S. paMescens, Dist., and S. pusana, 

 Dist., which w^ere present at the same period. A certain number of 

 Nephotettix were captured by light-traps and bagging, but the latter 

 method, being carried out in the flowering season, caused injury to the 

 flower-heads. Infestation as a whole was not severe, the late varieties 

 of rice being the most seriously injured. The advantage of sowing 

 early varieties appears to have been realised by cultivators, who do 

 not, however, apparently carry out control measures, such as bagging 

 or using light traps, w4th any degree of thoroughness. The follo\\ing 

 measures are recommended for controlhng Nephotettix : — (1) Bagging 

 the fields during July and August and again in the middle of 

 September ; (2) setting up lantern traps from the middle of September 

 to the end of October ; (3) increasing the area of early varieties of 

 rice under cultivation. 



The follo^\ing insect pests of sugar-cane were observed during the 

 course of the above investigations : — ScirpojjJiaga xanthogastreUa 

 (auriflua), the leaf-hoppers, Pyrilla aberrans, P. pusana and 

 P. perpusilla, and a species of Dascillid. The egg-masses of the 

 leaf-hoppers were heavily parasitised by a Chalcid. 



Davis (J. J.) & Satterthwait (A. F.). The False Cabbage Aphis 

 (Aphis pseudobrassicae, Davis). — Purdue Univ. Agric. Expt. Sta., 

 Lafayette, Ind., xviii, Bull. no. 185, May 1916, pp. 915-939, 

 7 figs., 4 tables. [Received 31st August 1916.] 



Aphis pseudobrassicae which occurs on various Cruciferous plants, has 

 a wide distribution in the United States, and has also been recorded from 

 Manitoba and South Africa. This species is hable to be confused with 

 A. brassicae in appearance and nature of injury. Experiments carried 

 out in order to determine the life-history in Indiana showed that the 

 average duration of hfe of the female is about 31 days. The period 

 between birth and maturity varied from 6 to 23 days, and the repro- 

 ductive period from 2 to 32 days. Natural enemies did not appear in 

 numbers sufficient to serve as a controlhng factor until late in autumn 

 after the crops had suffered injury. Diaeretus rajoae, Curt., and 

 Pachyneuron jnicans, How., were reared from this Aphid, while a species 

 of Aphidoletes and a Syrphid larva were predaceous on it. A fungus, 

 Empusa aphidis,wsLS prevalent divaong A. pseudobrassicae in late autumn. 

 The most efficient insecticide was tobacco extract (40 per cent.) used 

 at the rate of one part in 1,200 parts of water, with the addition of 

 4 lb. soap to each 50 U. S. gals, solution. This spray was apphed to the 

 lower side of the leaves, since the Aphids feed in that position. A 

 rotation of crops and the destruction of wild Cruciferous plants is 

 recommended . In greenhouses it can be controlled by sprapng or by 

 fumigation with hydrocyanic acid gas ; if the latter is used, 1 oz. 

 potassium cyanide or | oz. sodium cyanide should be allowed for every 

 3,000 cubic feet. Fumigation should be carried out when the tem- 

 perature is not higher than 65° F. 



