RECENT PAPERS IN THE ‘PHILOSOPHICAL TRANSACTIONS.’ 
A 574, 
A 575. 
A 576. 
A 577. 
A 578. 
A 579. 
A 580. 
A 581. 
B 365. 
B 366. 
B 367. 
B 368. 
B 369. 
B 370. 
B 371. 
B 372. 
Series A.—Mathematical and Physical. 
The Pressure upon the Poles of the Electric Arc. By W. G. Duffield, D.Sc., Professor of 
Physics, Captain, Royal Air Force, Thos. H. Burnham, B.Sc., and A. H. Davis, B.Sc., Post- 
Graduate Students in Physics, University College, Reading. Pp. 28. Price 3s. 
On Intensity Relations in the Spectrum of Helium. By T. R. Merton, D.Sc., Lecturer in 
Spectroscopy, University of London,!King’s College, and J. W. NICHOLSON, F.R.S., Professor 
of Mathematics in the University of London. Pp. 37. Price 3s. 6 d. 
The Scattering of Plane Electric Waves by Spheres. By T. J. I’A. Bromwich, Sc.D., F.R.S. 
Pp. 32. Price 3s. 
On the Fundamental Formulations of Electrodynamics. By G. H. LlVENS, University of 
Manchester. Pp. 39. Price 3s. 6d. 
The Influence of Molecular Constitution and Temperature on Magnetic Susceptibility. 
Part IV.—Further Applications of the Molecular Field. By Major A. E. Oxley, R.A.F., 
M.A., D.Sc., Mackinnon Student of the Royal Society. Pp. 43. Price 3s. 6 d. 
A Determination of the Deflection of Light by the Sun’s Gravitational Field, from Observations 
made at the Total Eclipse of May 29, 1919. By Sir F. W. Dyson, F.R.S., Astronomer Royal, 
Prof. A. S. Eddington, F.R.S., and Mr. C. Davidson. Pp. 43; 1 Plate. Price 4s. &d. 
A Critical Study of Spectral Series. Part V.—The Spectra of the Monatomic Gases. By 
W. M. Hicks, F.R.S. Pp. 134; 4 Plates. Price 8s. 
Title, Contents, Index, &c., Vol. 220. Pp. 10. Price 6d. 
Volume 220 (1920), 470 pp., with 5 Plates, Price £2 4s. 
Series B. — Biological. 
The Epithelial Sheath of Hertwig in the Teeth of Man, with Notes on the Follicle and 
Nasmyth’s Membrane. By J. Howard Mummery, D.Sc. (Hon.), M.R.C.S. Pp. 16 ; 2 Plates. 
Price 3s. 6 d. 
On Nerve-End Cells in the Dental Pulp. By J. Howard Mummery, D.Sc. (Hon.), Penn., M.R.C.S. 
Pp. 8; 2 Plates. Price 3s. 
The Transition from Rostro-Carinate Flint Implements to the Tongue-Shaped Implements of 
River-Terrace Gravels. By J. Reid Moir. Pp. 22; 7 Plates. Price 6s. 6 d. 
The Development of the Sea-Anemones Metridiurn Dianthus (Ellis) and Adamsia Palliata 
(Bohad). By James F. Gemmill, M.A., M.D., D.Sc. Pp. 25; 3 Plates. Price 4s. 
The Morphology and Evolution of the Ambulacrum in the Echinoidea Holedypoida. By 
Herbert L. Hawkins, M.Sc., F.G.S., Lecturer in Geology, University College, Reading. 
Pp. 104; 9 Plates. Price 8s. 6 d. 
On the Structure of Lysorophus, as Exposed by Serial Sections. By W. J. Sollas, Sc.D., 
F.R.S., Professor of Geology in the University of Oxford. Pp. 47 ; 1 Plate. Price 7s. 6 d. 
Title, Contents, Index, &c., Vol. 209. Pp. 10. Price &d. 
Volume 209 (1920), 530 pp., with 70 Plates, Price £3 13s. 
The Respiratory Exchange of Man During and After Muscular Exercise. By J. M. H. Campbell, 
O.B.E., B.M., C. Gordon Douglas, C.M.G., M.C., D.M., Fellow of St. John’s College, Oxford, 
and F. G. Hobson, D.S.O., B.M. Pp. 47. Price 5s. 
Cloth cases for binding the volumes of the ‘ Philosophical Transactions.’ Price 3s. 6 d. 
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