vi V Contents 



No. 4 (April, 1920) 



PAGE 



1. On the Relations between Orowth and the Environmental 



Conditions of Temperature and Bright Sunshine. By 

 Winifred E. Brenchley, D.Sc. (With 13 Text-figures) 211 



2. Ulonierella cingulata (Stoneman) Spauld. and v. Sch. and its 



Conidial forms, Glceosporium piperatum E. and E. and 

 Colletotrichum nigrum E. and Hals., on Chillies and Carica 

 papaya. Bv Jehangir Fardunji Dastur, M.8c. (With 

 Plate X) .' 245 



3. Field Experiments on the Chemotropic Responses of Insects. 



By A. D. Imms, M.A., D.Sc, and M. A. Husain, B.A. 



(With 1 Text-figure) 269 



4. On Forms of the Hop {Humulus Lupulus L. and H. ameri- 



canus Nutt.) Resistant to Mildew {Sphaerotheca Humuli 



(DC.) Burr.). By E. S. Salmon 293 



5. On the Sexual Forms of Aphis saliceti, Kaltenbach. By 



Maud D. Haviland . . . . . . . 311 



G. Proceedings of the Association of Economic Biologists . 314 



7. I. The Administrative Problem. By Sir A. D. Hall, 



K.C.B., F.R.S 317 



8. II. The Training Problem. By Professor V. H. Blackman, 



Sc.D., F.R.S 322 



9. III. The Agricultural Problem. By E. J. Russell, D.Sc, 



F.R.S 326 



10. IV. The Horticultural Problem. By F. J. Chittenden, 



F.L.S., V.M.H 330 



11. V. The Forestry Problem. By Professor W. Somerville, 



M.A., D.Sc, D.CEc 333 



12. VI. General Discussion ...... 339 



13. List of Members of the Association of Economic Biologists 



for 1920 349 



14. Laws of the Association of Economic Biologists . . 355 



