224 



the results of his iuvestigations upon the clioice of food exerted 

 by insects. He found that all the plants (various Cruciferae and 

 mignonette) which are fed upon by the larvae of Pleris hraifdcae 

 and P. rapae contain a particular glucoside, one of the mustaril 

 oils. He then smeared a dough of Bunias urientalis, which con- 

 tains this vsubstance, upon the leaves of a plant that the cater- 

 pillars had refused to eat; when thus treated the leaves were 

 eaten. Similar results were obtained in experiments with the 

 larvae of a herbivorous Hymenopteron, Priophorus padi, which is 

 attracted to members of the order Rosaceae, by the glucoside 

 amygdaline, that the plants contain. As regards the existence of 

 a ciiemotropic influence guiding the female where to lay her eggs, 

 in order that the young may hatch out upon suitable food 

 material, Howlett published some confirmatory results last year. 

 He succeeded in causing Sarcopliar/a to lay eggs in a bottle con- 

 taining skatol — a product of the decomposition of albuminous 

 material; and further, he caused Stomoxys calcitrans to oviposit 

 upon a cotton rag moistened with valerianic acid — a substance 

 resulting from the decomposition of vegetable matter. Dr. 

 Tragardh draws the conclusion that " the ovipositing of the 

 females is guided, even in those cases where the larva has a diet 

 different from that of tlie adult, by chemotropism." If tliis be 

 generally the case, a knowledge of chemotropism in insects should 

 afford an excellent means of controlling pests ; if the female could 

 be attracted to lay eggs elsewhere than on the plant which it 

 naturally attacks, a complete prevention of the pest would be 

 brought^ about. As yet very little work has been done upon 

 these lines, but it seems probable tliat the work of Verschaffelt, 

 Dewitz, and Howlett Avill prove to be of inestimable value to 

 economic entomologists. 



Coventry (B.). Report of the Director. — Report Agric. Researc]i 

 Ivst. c5- Coll., Pvm, 1911-1912, Calcvfta, 1913, pp. 10-11. 



Eeporting upon the work of the section of Pathological Ento- 

 mology, the Director says that special attention has been paid 

 to the genus Siegoinyia, and allied forms of mosquitos,_ owing 

 to the possibility of yellow fever being imported into India from 

 Panama. Other subjects receiving attention are the breeding 

 places and habits of Phlehofoimis, the life-history of the Crab- 

 louse (Phthirins pubis), the parasites of Tahnnus alhimedius, 

 Monophlebus stehhingi, and the life-history of Celypiiidae. The 

 East Indian Eailway school at Jharipani was successfully rid 

 of a plague of bugs by the application of hydrocyanic acid. 



Aphis-infested Rape and its Effect on Sheep.— A^?'ic. Gaz., N.S.W., 

 SyJnei/, xxiv, no. 9, Sept. 1913, p. 758. 



During the present year sheep were fed on aphis-infested rape, 

 to see if there was any truth in tlie supposition that the death 

 of certain sheep in 1911 was correlated with the infestation by 



