Contents. 
The Three-line Determinants of a Six-by-Three Array. By 
Thomas Muir, LL.D. Issued separately January 20, 1905, 
The Sum of the Signed Primary Minors of a Determinant. By 
Thomas Muir, LL.D. Issued separately January .20, 1905, 
Crystallographical Notes. By Hugh Marshall, D.Sc., F.R.S. 
Issued separately February 1, 1905, . . . 
The Effect of Simultaneous Removal of Thymus and Spleen in 
young Guinea-pigs. By D. Noel Pat on and Alexander Goodall. 
{From the Laboratory of the Royal College of Physicians , Edin- 
burgh.) Issued separately February 1, 1905, 
Networks of the Plane in Absolute Geometry. By Duncan M. 
Y. Sommerville, M.A., B.Sc., University of St Andrews. 
{Abstract.) . Communicated by Professor P. R. Scott Lang. 
Issued separately February 1, 1905, .... 
A Specimen of the Salmon in transition from the Smolt to the 
Grilse Stage. By W. L. Galderwood. (With Two Plates.) 
Issued separately February 1, 1905, .... 
A Comparative Study of the Lakes of Scotland and Denmark. 
By Dr C. Wesenberg-Lund, of the Danish Fresh- water Biological 
Station, Frederiksdal, near K. Lyngby, Denmark. Com- 
municated by Sir John Murray, K.C.B., F. E.S. {From the 
Danish Fresh-water Biological Laboratory, Frederiksdal.) (With 
Two Plates.) Issued separately March 3, 1905, . 
Variations in the Crystallisation of Potassium Hydrogen Succinate 
due to the presence of other metallic compounds in the Solution. 
{Preliminary Notice.) By Alexander T. Cameron, M.A. 
Communicated by Dr Hugh Marshall, F.R.S. Issued separately 
February 4, 1905, ...... 
A Laboratory Apparatus for Measuring the Lateral Strains in 
Tension and Compression Members, with some Applications 
to the Measurement of the Elastic Constants of Metals. By 
E. G. Coker, M.A. (Cantab.), D.Sc. (Edin.), F.R.S.E., Professor 
of Mechanical Engineering and Applied Mathematics, City and 
Guilds Technical College, Finsbury, London. (With a Plate.) 
Issued separately March 3, 1905, .... 
On Astronomical Seeing. By Dr J. Halm, Lecturer in Astronomy 
in the University of Edinburgh. Issued separately March 3, 
1905, . . . . . . ^ . 
On the Graptolite-bearing Rocks of the South Orkneys. By 
J. H. Harvey Pirie, B.Sc., M.B., Ch.B. Communicated by 
Dr Horne, F.R.S. With a Note by Dr Peach on Specimens 
from the South Orkneys. Issued separately March 30, 1905, . 
A Possible Explanation of the Formation of the Moon. By 
George Romanes, C.E. Issued separately March 30, 1905, 
On Pennella : a Crustacean parasitic on the Firmer Whale 
{Balcenoptera musculus). {Abstract.) By Sir William Turner, 
K. C.B., LL.D. Issued separately March 30, 1905, 
The Diameters of Twisted Threads, with an Account of the 
History of the Mathematical Setting of Cloths, By Thomas 
Oliver, B.Sc. (Lond. & Edin.).' Communicated by Dr C. G. 
Knott. Issued separately April 8, 1905, 
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