12. Mr. R. A. FISHER.-Incidence of Rainfall in Relation to the Wheat Crop.

13. Dr. G. P. McROSTIE.-Some Forage Crop Needs and Difficulties in Canada.

14. Mr. F. L. ENGLEDOW.-A Spacing Experiment with Wheat.

The experiment was one of a series aimed at the identification of those characters of different wheat forms by which their yielding capacities are mainly controlled. True plant characters-the vital processes-are not sufficiently understood to be the subject of such an inquiry. Consequently algebraic characters like tillering and ear size were observed. Such characters are much affected by inter-plant spacing, and that is the first ground of necessity for making spacing experiments. The second is the fact that field crops, inevitably, are aggregates of a great number of spatial intervals. Plant growth and yield in the field consequently must depend largely upon the adaptability of each particular wheat form to the various spacing intervals encountered in field crops.

Two wheats were grown each at five spacings, and special measures were taken to secure uniformity of material.

Analytical data are produced to show that :—

1. The variability of yield per plant and yield per unit area with spacing can be resolved in terms of tillering, ear size, and grain size.

2. Ear size and grain size bear distinctive relations to tillering which are characteristically different in the two wheats.

3. Data of the kind discussed appear to offer an approach to the differences in yielding capacity displayed by the various forms of wheat in the field. Upon the discovery of these differences must depend the possibility of breeding higher yielding forms by orderly synthetic' aggregation of desirable characters by means of hybridisation.

15. Dr. G. SCOTT ROBERTSON.-Field Experiments with Rock Phosphates on Soils Poor in Phosphoric Acid.

The paper gives an account of a number of field experiments carried out in the six counties of Northern Ireland to ascertain the fertilising value of ground rock phosphates compared with high grade basic Bessemer slag and superphosphate.

The experiments were carried out during the years 1921, 1922, and 1923, and are still in progress. The crops were turnips, potatoes, oats, and hay. The results show that on the turnip crop as good returns may be expected, on all but peaty soils, from ground rock phosphates as from superphosphate or high-grade slag. Contrary to expectations, superphosphate proved the most effective type of phosphate on peaty soils. On potatoes superphosphate proved to be decidedly the better phosphate. On the oat crop the best returns were given by basic slag, rock phosphate and superphosphate being equally good and not far behind the slag.

The experiments confirm the view that ground rock phosphates may, under the soil and climatic conditions of Northern Ireland, be regarded as an effective substitute for the rapidly disappearing high-grade basic slag. It is possible that the effectiveness of rock phosphates on the potato crop may be enhanced by still finer grinding.

Wednesday, August 13.

16. Joint Discussion with Section K (q.v.) on Forest Problems in Canada. (Page 454.)

REFERENCES TO PUBLICATION OF COMMUNICATIONS TO THE SECTIONS

AND OTHER REFERENCES SUPPLIED BY AUTHORS,

Under each Section, the index-numbers correspond with those of the papers in the sectional programmes (pp. 358-463).

References indicated by 'cf.' are to appropriate works quoted by the authors of papers, not to the papers themselves.

General reference may be made to the issues of Nature (weekly) during and subsequent to the meeting, in which resumés of the work of the sections are furnished.

SECTION A.

1. Cf. The Spectrum of trebly-ionised Silicon,' in Proc. Roy. Soc., 103, p. 413; further material to be published in the same.

2. Paper under same title to be published as bulletin of Nat. Research Council, U.S.A. Cf. 'Soft x-rays from arcs in gases,' Bureau of Standards Sci. Papers, No. 425; 'Enhanced spectra of Na and K in the low voltage arc,' Astrophys. Journ. 55, pp. 145-161 (1922).

4. Cf. Phil. Mag., 47, p. 257 (1924); Proc. Camb. Phil. Soc., 22, p. 253 (1924); E. A. Milne in Phil. Mag., 47, p. 209 (1924).

8. Journ. Optical Soc. Amer., 7, pp. 583, 913; Amer. Journ. Physiol. Optics, 5, July, Oct.

11. Cf. Transmission of Sound by Flexible Materials,' Amer. Architect, Sept. 28 and Oct. 12, 1921; Nature and Reduction of Office Noises,' ibid., May 24, June 7 and 21, 1922; 'Transmission of Sound by Masonry Partitions,' ibid., July 4, 1923. 12. Nature, Nov. 8, 1924, p. 684.

15. Expected to be published in Phil. Mag. Cf. ibid., Oct. 1913; Franklin Inst. Journ., Nov. 1920; Phys. Rev., Apr. 1922; Trans. Roy. Soc. Can., 1922, 1923. 20. To be published in Monthly Weather Review.

21. A paper to appear shortly in Geofysiske Publikationer, Kristiania; cf. ibid., 1, no. 2; 2, no. 3; 3, no. 1.

23. Cf. Phil. Trans., 221A, pp. 239-264 (1920).

26a. Cf. 'Structure of Aragonite,' in Proc. Roy. Soc., A, 105; 'Refractive indices of Calcite and Aragonite,' ibid.; Influence of Atomic Arrangement on Refractive Index,' ibid. 106 (1924).

26c. Cf. Müller in Trans. Chem. Soc., 123, p. 2043; Shearer, ibid., p. 3152; Müller and Shearer, ibid., p. 3157 (1923); further results to be published, ibid.

26d. Cf. A Theoretical Calculation of the Rhombohedral Angle of Crystals of the Calcite Type,' in Proc. Roy. Soc., A, 106 (1924).

26e. Cf. (for first part) Phil. Trans., A., 224, pp. 251-257; second part to be published, ibid.

28. Journ. Soc. Chem. Ind., Aug. 29, 1924. Cf. Reports of Advisory Committee on Atmosphere Pollution.

30. To be published in Monthly Weather Review, and Trans. Illuminating Engineering Soc., N.Y. Cf. H. H. Kimball and I. F. Hand, ‘Sky-Brightness and daylight illumination measurements,' Monthly Weather Review, 49, pp. 481-488 (Sept. 1921); Trans. Illuminating Eng. Soc., 16, pp. 255-283 (Oct. 10, 1921); 'Daylight illumination on horizontal, vertical and sloping surfaces,' Monthly Weather Review, 50, pp. 615-628 (Dec. 1922); Trans. Illuminating Eng. Soc., 18, pp. 434-474 (May, 1923); H. H. Kimball, The determination of daylight intensity at a window opening,' Trans. Illuminating Eng. Soc., 19, pp. 217-234 (Mar. 1924).

31. To be published probably in book form with other papers.

346. To be published in Journ. Phys. Chem., s.n. C. Sweitzer. Cf. Kenrick, Scattering of light,' in Trans. Roy. Soc. Can., 15, 48 (1921), and J. Phys. Chem., 26, 72 (1922); Wismer, 'Pressure-Volume relations, etc.,' in Trans. Roy. Soc. Can., 15, 48 (1921), and J. Phys. Chem., 26, 301; Gilbert, 'Superheating, etc.,' in Trans. Roy. Soc. Can., 15, 53 (1921); Wismer, 'Supersaturation of gases, etc.,' in Trans. Roy. S. Can., 16, 271.

34c. To be published in Journ. Phys. Chem. Cf. Journ. Phys. Chem., 24, p. 478 (1920); 26, pp. 75, 471 (1922); 27, p. 558 (1923); Trans. Roy. Soc. Canada, 16, iii, p. 276 (1922); 17, iii, p. 151 (1923).

35. A paper on the subject to be published in Phil. Mag.

36. Main portion to be published in Journ. Franklin Inst.

37. Cf. The 27-day Period (Interval) in Terrestrial Magnetic Disturbance,' Proc. Roy. Soc., A, 106, pp. 19-32 (1924); The Magnetic Disturbance, 1924, January 29-30,' Monthly Notices R.A.S., 84, pp. 531-532.

38. To appear in Publications of Dominion Obs., and probably in Journ. R.A.S.C.

48. Publications of Dominion Astrophys. Obs., 3, no. 1.

49. To appear as Publications of Dominion Obs., 9, no. 2; cf. ibid., 5, no. 8, no. 4; Lick Obs. Bull., 9, p, 173.

50. To appear in substance in Publications of Dominion Obs. Cf. Pub. Amer. Ast. Soc., 4, pp. 185, 237, 390; Journ. R.A.S.C., 1922, p. 121; 1923, pp. 10, 79, 109, 247, 383; 1924, p. 271.

SECTION B.

2. Cf. Bone, Newitt, and Townend in Proc. Roy. Soc., A, 103, p. 205 (1923); ibid., 105, p. 406 (1924).

4. Expected to be offered for publication in Trans. Chem. Soc.; for other references cf. J.C.S. Trans., 1921.

5. Expected to be published in Journ. Soc. Chem. Ind.

6. To be published in Canadian Chemistry and Metallurgy, and in Industrial and Engineering Chemistry (U.S.A.).

13d. Cf. Bone, Cantor lectures pubd. in Journ. Roy. Soc. Arts, 1922; id., Proc. Roy. Soc., A, 99, p. 236 (1921).

14a. To be published in Canadian Chemistry and Metallurgy; cf. ibid., 8, no. 8, p. 194; no. 9, p. 208 (1924).

14h. Kenrick, Gilbert, and Wismer, 'Superheating of Liquids,' and Kenrick, Wismer, and Wyatt, Supersaturation of Gases in Liquids,' in Journ. Phys. Chem., Nov. 1924.

SECTION C.

1b. Cf. Annual Reports, Ontario Dept. of Mines.

4. Cf. Some features of the Kansan drift of southern Iowa,' in Geol. Soc. Amer. Bulletin, 27, pp. 115-17 (1916); ‘Gumbotil, a new term in Pleistocene geology,' in Science, n.s., 44, pp. 637-8 (Nov. 3, 1916); Pleistocene deposits between Manilla in Crawford county and Coon Rapids in Carroll county,' Iowa Geol. Surv., 26, pp. 215231; also abstract Iowa Acad. Sci. Proc., 24, pp. 99-100 (1917); also Bull. Geol. Soc. Amer., 29, 18; 'The Origin of Gumbotil' (with J. N. Pearce), in Jour. Geol., 28, no. 2, pp. 89-125 (Feb.-Mar. 1920); 'Significance of the relation of Proboscidean remains to the surface of Nebraskan Gumbotil, near Osceola, Clarke county, Iowa, in Bull. Geol. Soc. Am., 32, pp. 81-83 (1921); 'A comparative study of the Nebraskan and Kansan tills in Iowa,' ibid., 33, p. 115 (Mar. 1922); 'Recent studies of the Pleistocene in western Iowa,' ibid., 35, pp. 71-73; A new interpretation of the type sections of Aftonian gravels in Iowa,' in Journ. Geol. (in press).

5. Cf. Dinosaurs of Alberta,' in local Handbook for meeting; Dyoplosaurus acutosquameus and Notes on Prosaurolophus Maximus,' Univ. of Toronto Studies (in press, Sept. 1924).

6. Cf. paper on 'Cothurnocystis,' to appear in Paleontologische Z., 1925. 11. Univ. of Toronto Studies, Geol. Series, 17. Cf. South Lorrain Silver District, Ont.,' Trans. Amer. Inst. Mining and Met. Eng., Jan. 1924; 'Deep-seated oxidation 1924

H H

and secondary enrichment at Keeley Silver Mine,' Econ. Geol., 18, vii (1923); 'Occurrence of silver ores in South Lorrain, Ontario, Canada,' Bull. Inst. Mining and Metal., Feb. 1922.

12. Mineralog. Mag., 20 (1925).

21b (e). Subject expected to be published in Amer. Journ. Sci. and Bull. Geol. Soc. Amer. Cf. Journ. Geol., 32, no. 4, May-June, 1924.

21b (g). To be published in Econ. Geol.

25. To be published in Journ. Geol. (Chicago).

26. To be presented to Geol. Soc., London.

SECTION D.

5. Expected to be published in Journ. Genetics or Brit. Journ. Exper. Biol. Cf. Brit. Journ. Exper. Biol., 1, i (1923).

6. Cf. Proc. Roy. Soc., B, 95 (1923); Brit. Journ. Obstet. and Gynecol., Oct. 1924. 9. Expected to be published in Brit. Journ. Exper. Biol.

11. Probably to be published in Bull. Entom. Research. Cf. 'Some Blood-sucking Flies of Saskatchewan,' in Agric. Gaz. Canada, 5, no. 6 (1918).

16. To be published in fuller detail in Journ. Comparative Neurology. Cf. On the Relative Vascularity of Various Parts of the Central Nervous System of the Albino Rat,' in Journ. Comp. Neur., 31, pp. 429-464 (1920); The Vascularity of the Cerebral Cortex of the Albino Rat,' ibid., 33, pp. 193-212 (1921).

22. Cf. Univ. of Toronto Studies; papers of Ont. Fisheries Research Lab.

23. Cf. Rate of growth and food of the lake sturgeon,' Pubns. of Ontario Fisheries Research Lab., 17-21 (Biol. Series, Univ. of Toronto).

31. Intended to be presented to Proc. Zool. Soc., London.

SECTION E.

1. To be published in Scot. Geog. Mag.

3. Leaflet and publications of Permanent Committee on Geographical Names, Roy. Geog. Soc., London.

8. Cf. 'Magnetic observations in Western Canada,' Topog. Surv. of Canada Bull., 46; 'Magnetic results in Western Canada,' ibid., 52; 'Diurnal inequality of Declination at Aklavik, N.W.T.,' Journ. Roy. Astron. Soc. Canada (June-July, 1924), and other articles, ibid.

10. Cf. Trans. Roy. Soc. Canada, 4, iii, N.S., 1910.

14. Cf. The Rôle of the Glacial Anticyclone in the Air Circulation of the Globe,' in Proc. Am. Phil. Soc., 54, Aug. 1918, pp. 185-225; The Fixed Glacial Anticyclone compared to the Migrating Anticyclone,' ibid., 60, 1921, pp. 34-42; The Mechanics of the Glacial Anticyclone illustrated by Experiment,' Nature, July 22, 1920.

18. To be published in Scot. Geog. Mag. Cf. The Ituri Forest, River, and Pygmies,' in Geog. Journ., 46, no. 3 (1915); 'The Bahr el-Ghazal and its Waterways,' ibid., 61, no. 5 (May 1923); Big Game and Pygmies (Macmillan, 1924).

19. To be published in Amer. Geog. Review.

20. To be published in Scot. Geog. Mag.

23. Cf. Subdivision of N. America into Natural Regions: a preliminary enquiry,' Ann. Assoc. Amer. Geographers, 4, pp. 55-83 (1914).

SECTION F.

26. To be published in Metron (Ferrara, Italy).

3. See Presidential Address to Roy. Statist. Soc., Nov. 1924, to be published in Society's Journ.

6. To be published more fully in Journ. Pol. Econ. Cf. The Progress of Economics,' in Q.J. Econ., 26, pp. 1-67,

7. Financial News, Aug. 25, 26 (1924).

8a. Nature, Nov. 8, 1924.

106. Expected to be published in Brit. Econ. Journ., Mar. 1925. Cf. paper privately printed by author: Chicago Wheat Prices for Eighty-one Years': 'Wheat Prices and Wheat Receipts in Chicago-Their Correlation for Ten Crop Years, July 1, 1904, to June 30, 1914'; 'Cost of Marketing Grain '; 'The Law of Supply and Demand and the Wheat Market'; 'The Chicago Board of Trade-What it is and what it does.'

2. Engineering, Aug. 22, p. 266.
3. Engineering, Aug. 22, p. 266.

SECTION G.

4. Engineering, Aug. 29, p. 301. p. 301; cf. paper at World Power Conference, London, July 1924.

Canadian Engineer, Aug. 19, 1924; Aug. 29,

5. Engineering, Aug. 15, p. 193; Aug. 22, p. 255.

'

6. Engineering, Aug. 15, p. 239; Aug. 22, p. 271; Canadian Engineer, Aug. 19, p. 26, 1924; reprint from latter obtainable from author, 340 University Street, Montreal, 7. For Mr. Kimball's contribution, cf. Stress in Railway Motor Pinions,' in Trans. Amer. Soc. Mechan. Eng., 1922; Gen. Elec. Rev., Feb. 1924; Stress Determination by means of the Coker Photoelastic Method,' in Gen. Elec. Rev., Jan. 1921; P. Heymans and Kimball, Stress Distribution in Electric Railway Motor Pinions as determined by the Photoelastic Method,' ibid., Mar. 1923.

8. Engineering, Aug. 29, p. 284.

9. Engineering, Aug. 15, p. 245.

10. Engineering, Aug. 29, p. 284; Oct. 1924.

11. Engineering, Aug. 29, p. 286.

12. Engineering, Aug. 29, p. 284.

13. Engineering, Sept. 15, p. 343.

14. Engineering, Aug. 29, p. 286. 16. Engineering, Aug. 29, p. 286.

17. Engineering, Aug. 15, p. 241.

18. Engineering, Aug. 22, p. 274; Aug. 29, p. 302; cf. 'Permanent Magnets, and the relation of their properties to the constitution of Magnet Steels,' in Journ. Inst. Elec. Eng., 61, no. 319.

19. Engineering, Aug. 29, p. 287.

20. Engineering, Aug. 22, p. 257.

SECTION H.

1. See Haddon, The Races of Man and their Distribution, Cambridge Univ. Press, 1924 (pp. 139-157).

2. Proc. Roy. Soc. Canada, 1921-22, and Presidential Address to Section II., ibid., 1923.

6. Cf. Year's Work in Classical Studies, 1922-3, pp. 97-116; The T'imes Lit. Supp., Jan. 10, 17, 1924.

7. Cf. Papers of Brit. School at Rome, 1 (pp. 125-285), 3 (1-212), 4 (1-159), 5 (213-432), 8 (104-171), with Mr. R. Gardner; Journ. Roman Studies, 11, pp. 125-190 (1921), with Mr. R. A. L. Fell.

10. To be published in American Anthropologist.

11. Classical Philology (Univ. of Chicago Press), Jan. 1925.

16. Cf. Proc. Ninth Internat. Congress of Americanists, Wash., 1917; revised in current Annual Rep. of Smithsonian Inst.

21. To be published in Journ. Phys. Anthrop., Washington.

23. To be published in Man,