250 EXPERIMENT STATION BECORD. 



The injury occasioned by tlie insect is caused tlirough puncturing and suck- 

 ing tlie juices from the leaves and tender stalks. The first appearance of the 

 injuiy is usually noticed on the upper surface of the midribs, near their junc- 

 tion with the stalks, the punctures in these tissues appearing as small whitish 

 spots. Within a few days after the attack the leaves on these stalks become 

 parched and dry and the entire stalk has the appearance of having been killed 

 by a heavy frost. In cases where the infestation is lighter only the buds and 

 upper portion of the stalks are killed, leaving some of the lower leaves still 

 green, and where it is very light the foliage turns yellow. 



At Marion eggs deposited September 5 hatched 9 days later, and the nymphs, 

 after molting 5 times, became mature on September 30, thus completing the life 

 cycle from egg to maturity in 25 days. 



A 10 per cent kerosene emulsion or whale-oil soap at the rate of 1 lb. of 

 soap to 5 gal. of water is recommended as a control measure. 



Since it is a habit of this insect to pass the fall and early winter under 

 shucks on Uie old cornstalks remaining in the fields and gardens, cutting .nnd 

 plowing under all the stalks immediately after the corn has been harvested is 

 found to be an important control measure. 



The rose aphis, H. M. Russell {U. S. Dept. Agr. Bui. 90 (1914), pp. 15, pis. S, 

 figs. 4). — This bulletin reports the results of studies that were commenced in 

 Los Angeles in 1910 and later carried on to some extent at Washington, D. C. 



The rose aphis is said to be distributed over the entire United States and also 

 occurs in Europe, from which country it was first described. Observations of 

 its life history, both at Log Angeles and in a greenhouse at Washington, D. C, 

 are reported. It is estimated that in greenhouses there are from 25 to 30 

 generations annually and in the open 12 or more. 



Under natural control mention is made of rains, heat, birds, and parasitic 

 and predaceous insects. A braconid (Ephedrus incompletus) was reared from 

 the aphis at Washington, D. C, in 1912. During the year 1910 five different species 

 of Syrphidiie were reared from the larvae feeding on this aphid, namely, Syrphus 

 ribesii, S. opinator, AUograpta frocta, Eupeodes volucris, and Lasiophthiciis 

 pyrasti. 



In the experiments reported nicotin sulphate at a dilution as high as 1 : 1400 

 was much more effective against the rose aphis when used in combination with 

 whale-oil or other soap, since the spreading action thus induced is much more 

 favorable. It was found that in the greenhouse lower strengths of nicotin sul- 

 phate can be used, and that 1 part to 2,000 of water will not injure the rose 

 plant if applied on a dark day or late in the afternoon so that the plants will 

 not be exposed to reflected sunlight through the glass. 



The cotton root louse (Aphis maidi radicis), W. A. Thomas (South Carolina 

 Sta. Bui. 115 (1914), PP- 3). — A brief popular account of this cotton pest. 



On the biology of aphidid pests of tree and bush fruits, V. V. Dobrov- 

 LiANSKY (K Biologii Tlcl Plodovykh Dercv'ev i lagodnykh Kustov. Kief: Kiev 

 Etit. Stantsiia lazh. Russ. Obshch. Pooshch. Zeml. i Selslc. Promysh., 1913, 

 pp. JfS; ahs. in Rev. Appl. Ent., 2 (1914), Ser. A, No. 2, pp. 19-82). — A report of 

 studies made in the vicinity of Kief in 1914, particularly of Aphis pomi. 



Plant louse notes from California, W. M. Davidson (Jour. Econ. Ent., 7 

 (1914), No. 1, pp. 121-136, figs. 8). — Descriptive notes on a number of species, 

 including several new to science. 



The life history of the sugar beet root louse (Pemphigus betae), J. R. 

 Parker (Jour. Econ. Ent., 1 (1914), No. 1, pp. 136-141). — "Wingless viviparous 

 females are found in the ground the year around upon the roots of beets, 

 weeds, and grasses. In the fall winged individuals are produced which fly to 

 Cottonwood trees and deposit the true sexes. The sexes mate and the female 



