vi CONTENTS. 
VII. On the Cranial Osteology of Rhizodopsis. By Ramsay H. 
Traquair, M.D., F.R.S., Keeper of the Natural History Col- 
lections in the Museum of Science and Art, Edinburgh, 
VIII. On the Action of Phosphide of Sodium on Haloid Ethers and on 
the Salts of Tetrabenzyl-Phosphonium. By Professors LErrs 
and N. Cot.tr, Esq., F.R.SS. L. & E.,, 
IX. On the Geology of the Ferée Islands. By James Geixte, LL.D., 
F.R.SS. L. & E. (Plates XIII. to XVI), 
X. Researches in Contact Electricity. By Carcitt G. Knott, D.Se. 
Communicated by Professor Tarr. (Plate XVII), 
XI. On Phosphorus-Betains. By Professor Letts. (Plate X VIIL), 
XII. On Dust, Fogs, and Clouds. By JouHn AITKEN, 
XIII. The Effect of Permanent Elongation on the Specific Resistance of 
Metallic Wires. By Tuomas Gray, B.Sc., Demonstrator in 
Physics and Instructor in Telegraphy, Imperial College of 
Engineering, Tokio, Japan. (Plate X VIIIa), . 
XIV. On the Histology of the Pedicillarie and the Muscles of Echinus 
spheera (Forbes). By Patrick Greppss, F.R.S.E., Lecturer on 
Zoology in the School of Medicine, Edinburgh ; and Franx E. 
Bepparp, B.A., Assistant Demonstrator of Zoology, Oxford. 
(Plates XIX. to XXI.), 
XV. On some New Species of Fossil Scorpions from the Carboniferous 
Rocks of Scotland and the English Borders, with a Review of the 
Genera Eoscorpius and Mazonia of Messrs Meek and Worthen. 
By B. N. Peacu, A.R.S.M., F.R.S.E., of the Geological ee 
of Scotland. (Plates XXII. and XXIIL ), ; 
XVI. Effects of Strain on Electric Conductivity. By Avueust Wit- 
KOWSKI. Communicated by Sir WiLL1AM THomson, ; 
XVII. On the Constitution of the Lines forming the Low-Temperature 
Spectrum of Oxygen. By Piazza Smytu, Astronomer-Royal 
for Scotland, 
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