VI 
Contents. 
PAGE 
On Tetrabothrium torulosum and Tetrabothrium auriculatum. By 
Dr 0. von Linstow, Gottingen. Communicated by Sir John 
Murray, K.C.B., ....... 158 
Contributions to the Craniology of the People of India. Part 
II. — The Aborigines of Chuta Nagpur, of the Central Provinces 
and the People of Orissa. ( Abstract .) By Professor Sir 
William Turner, F.R.S., ...... 161 
The Action of Silver Salts on Solution of Ammonium Per- 
sulphate. By Hugh Marshall, D.Sc. (With a Plate), . .163 
Hyperbolic Quaternions. By Alexander Macfarlane, Lehigh 
University, South Bethlehem, Pennsylvania. (With a Plate), 169 
The Theory of Skew Determinants and Pfaffians in the Historical 
Order of its Development up to 1857. By Thomas Muir, 
LL.D., 181 
On the Motion produced in an Infinite Elastic Solid by the 
Motion through the Space occupied by it of a body acting on it 
only by Attraction or Repulsion. By Lord Kelvin, . . 218 
The Total Solar Eclipse of 28th May 1900. By Thomas Heath, 
B.A., 236 
A Peculiar Set of Linear Equations. By Thomas Muir, LL.D., . 248 
Note on Dr Muir’s Paper on a Peculiar Set of Linear Equations. 
By Charles Tweedie, M.A., B.Sc., .... 261 
Note on Pairs of Consecutive Integers the Sum of whose Squares 
is an Integral Square. By Thomas Muir, LL.D., . . 264 
The Seaweed JJlva latissimi, and its relation to the Pollution of 
Sea Water by Sewage. By Professor Letts and John 
Hawthorne, B.A., Queen’s College, Belfast. (With Three 
Plates), ........ 268 
Solar Radiation and Earth Temperatures. By Professor C. G. 
Knott. (With a Plate), ...... 296 
Change of the Coefficient of Absorption of a Gas in a Liquid with 
Temperature. By Professor Kuenen. (With a Plate), . 312 
Simple Proof of Gibbs’ Phase-rule. By Professor Kuenen, . 317 
The Biology of the Genus Pissodes. (George Heriot Research 
Fellowship Thesis.) By R. Stewart MacDougall, M.A., D.Sc. 
Communicated by Professor Cossar Ewart, . . .319 
The Biology and Forest Importance of Scolytus (Eccoptog aster) 
multistriatus (Marsh). By R. Stewart MacDougall, M.A., D.Sc. 
Communicated by Professor Cossar Ewart, . . . 359 
Note on the New Star in Perseus. By the Astronomer-Royal for 
Scotland. (With a Plate), ..... 365 
Additional Note on the Ultra-Neptunian Planet, whose existence 
is indicated by its action on Comets. By Professor George 
Forbes, M.A., F.R.S. (With a Plate), . . . .370 
On Hair in the Equidse. By F. H. A. Marshall, B.A., F.R.S.E. 
(With Six Plates), ...... 375 
