364 



PiERSON (H. B.). An infestation of the White Pine Aphid. — Psyche^ 

 Boston, Mass., xxvii, nos. 2- 3, April-June 1920, pp. 62-63. 



This paper records an attack of white pine trees by LacJmus strobi. 

 Fitch (white pine aphis). Mature trees in a somewhat isolated clump 

 were all dying as a result, while the infestation was spreading to young 

 plantations on the sides. The Aphids were ovipositing on the needles 

 on 10th October, and their survival in spite of low temperatures and 

 heavy rains was remarkable, subsequent examinations showing that 

 they were feeding imtil about the first of November. Very few winged 

 individuals were found. 



Gaeman (H.) & Jewett (H. H.). The Broods of the Tobacco Worms.. 



— Univ. Kentucky Agric. Expt. St a., Lexington, BuU. 225, March 

 1920, 24 pp., 4 figs. [Received 29th June 1920.] 



Of the two moths, Protoparce (PJilegethontius) sexta (southern tobaccO' 

 worm) and P. celeus (northern tobacco worm), the former is constantly 

 injurious to tobacco, while the latter only occurs in certain seasons and 

 is local, though both fluctuate widely in numbers in difierent years. 

 Their hfe-histories are identical in Kentucky within a week or two. 

 Larvae of the first brood appear about the time the tobacco plants are 

 transplanted. The second brood appears early in August, but there is- 

 considerable overlapping and all stages may appear at any time between 

 late June and the end of August. Whether individuals observed late 

 in the year belong to a third brood or are belated members of the second 

 is uncertain. 



For control to be effective arsenites should be appHed when the- 

 larvae are young — as soon as possible after hatching. There are thus 

 two periods of importance, from the middle to the end of June and early 

 in August. 



Fungi, insect parasites and diseases cause wide fluctuations in the 

 number of caterpillars from season to season. The more important, 

 are a fungus, apparently Cordyceps militaris, which attacks the pupae, 

 a disease of uncertain origin which attacks aU larvae in tobacco fields, 

 a Hymenopterous parasite, Apanteles congregatus, and a fly, Winthemia. 

 quadripustulata. 



Weigel (C. a.). & Sanford (H. L.). Chrysanthemum Midge. — TJ.S.. 

 Dept. Agric., Washington, D.C., Bull. 833, 31st May 1920, 25 pp.,. 

 2 plates, 2 figs. 



Diarthronomyia hypogaea, Lw. (chrysanthemum midge), although 

 of comparatively recent introduction into the United States, is now 

 one of the most important pests of chrysanthemums, attacking both, 

 greenhouse and outdoor plants. The average Hfe-cycle requires about 

 35 days and there are several generations in greenhouses, occurring: 

 during the spring (February to June) and during the autumn (Septem- 

 ber to November). Natural enemies that have been recorded include- 

 Amblymerus sp., the larvae of which Uve within the galls occupied by 

 the maggots of the midge, which they consume. They remain within 

 the galls until mature, adults appearing from August to October,, 

 during which time as many as 80 to 90 per cent, of the maggots may 



