299 



Shinji (G. 0.). A Contribution to the Physiology of Wing Development 

 in Aphids. — Biol. Bull. Marine Biol. Lab., Woods Hole, Mass. ; 

 Lancaster, Pa., xxxv, no. 2, August 1918, pp. 95-116. [Received 

 20th May 1919.] 



The author's summary of this paper is as follows . — (1) Either an 

 apterous or an alate parthenogenetic female may bear young larvae, 

 some of which may finally attain the winged condition, while others 

 may remain wingless throughout life. (2) When newly born Aphids 

 were reared on rose twigs planted in tumblers containing washed and 

 sterilised sand that had previously been saturated with the solution 

 of a certain substance, nearly 100 per cent, of winged individuals 

 appeared on the twigs, while either none or few winged forms developed 

 on the twigs charged wdth any one of another set of chemicals. (3) As 

 far as the tests go, the salts of the allcalis and alkaline earths with 

 the exception of magnesium, distilled w^ater, urea, alum and others 

 were shown to belong to the non-wing-developing substances, while 

 the salts of the heavy metals and of magnesium, sugar and perhaps 

 some others, belong to the category of wing-developing substances. 

 (4) The wing-developing substances were only effective when applied 

 within a certain period after birth. This period varied with tempera- 

 ture and also with the species, e.g., the maximum time for the rose 

 aphis, Macrosiphum rosae, L., during the early summer was found 

 to be from 2-3 days, while under the same conditions from 5-7 days 

 was the maximum in the case of M. solanifolii, Ashm., Ajjhis brassicae, 

 L., etc. (5) The amount of magnesium salts and also of other wing- 

 developing substances needed to produce winged Aphids was very 

 small. Subjection to a m/100 solution of magnesium sulphate for 

 12-24 hours produced nearly 100 per cent, of winged Aphids, so far 

 as M. rosae was concerned. (6) WTien twigs planted in the sand 

 saturated with distilled water and calcium chloride were subjected to 

 a drying process, the young Aphids born on these twigs remained 

 apterous, whereas on those that had been charged with solutions of 

 magnesium salts or some other wing-developing substances, the 

 greatest number of the winged Aphids appeared. (7) \\'Tien newly 

 born Aphids are subjected to a mixed solution of wing-developing and 

 non-wing-developing substances, winged Aphids may or may not 

 appear, according to whether or not the solution contains an excess 

 of the wing-developing over the non-wing-developing substances. 

 (8) Variation in temperature, or a sudden change from as high as 

 100° F. to as low as 35° F., failed to produce winged Aphids on the 

 twigs charged with non-wing-developing substances. 



The popular conception that the approach of cold weather makes 

 winged Aphids appear may be explained by the fact that plants 

 mature at this time and in so doing manufacture starch which is 

 changed into sugar for transference to storage organs, and this sugar 

 is the most common wing-developitig substance. 



SwAiNE (J. M.). The Balsam Injury in Quebec and its Control.— 



Agric. Gaz. Canada, Ottawa, vi, no. 3, March 1919, pp. 227-233, 

 3 figs. [Received 21st May 1919.] 



About 10 years ago, an outbreak of the spruce bud-worm [Tortrix 

 fumiferana] developed in the province of Quebec, affecting the spruce 

 (0571) ci 



