Contents. 
vii 
PAGE 
The histology of the early placenta of Macacus nemestrinus. (With 
Plates IV — XI.) By W. L. H. Duckworth 299 
On the theory of the rotation of the plane of polarization by solutions. 
By Prof. J. J. Thomson 313 
Proceedings at the Meetings held during the Session 1906 — 1907 . . 318 
A critical description of three cases of Single Hypogastric artery in the 
Human Foetus. (With Plates XII and XIII.) By W. L. H. Duck- 
worth . 325 
On the Fatigue of Metals subjected to Radium Rays. By J. A. Crowther 340 
The Orientation of a Series of substituted Bromanilines. By J. R. Htll. 
(Communicated by H. 0. Jones) ....... 351 
The decomposition and nitrification of seivage (1) in alkaline solutions , 
(2) in distilled water. By J. E. Purvis and R. M. Courtauld . 354 
The influence of light and of copper on fermentation. By J. E. Purvis 
and W. A. R. Wilks 361 
Sexual Phenomena in the Free-living Nematodes. By F. A. Potts . 373 
Resolution of Optically active Ammonium Salts by means of Tartaric 
Acid. By H. O. Jones 376 
Studies on Platinocyanides. By L. A. Levy ...... 378 
The absorption spectra of collidine and Q-chlor-collidine. By J. E. 
Purvis and W. H. Foster 381 
1 he Action of metallic Magnesium on certain aliphatic acids , and the 
detection of Formic acid. By H. J. H. Fenton and H. A. Sisson . 385 
Some colour -reactions of organic acids with Phenols. By H. J. H. 
Bar Fenton and G. Barr 386 
Ail example of complex double integration. By A. C. Dixon . . . 388 
On a new genus of Ixodoidea together with a description of eleven new 
species of ticks. By Prof. George H. F. Nuttall and Cecil 
Warburton 392 
On the ionization of Gases by Ultra- Violet Light and on the evidence as 
to the structure of light afforded by its Electrical Effects. By Prof. 
J. J. Thomson 417 
Note on a method of demonstrating the syncytial appendages of the 
placental villi. (With Plate XIV.) By W. L. H. Duckworth 425 
On the Intestinal Protozoan Parasites of Frogs and Toads. (Preliminary 
Co; amunication.) By C. C. Dobell ...... 428 
The aba option spectra of some compounds obtained from pyridine and 
collidine. By J. E. Purvis 435 , 
The limitations of the copper-zinc couple method in estimating nitrates. 
By J. E. Purvis and R. M. Courtauld 441 
Description of a microcephalous new-born pig in which the face and the 
fore-parts of the brain were undeveloped , and the bucco-pharyngeal 
membrane remained imperforate. (With Plates XV and XVI.) By 
W. L. H. Duckworth 447 
On six new species of Ixodidae, including a second species of the new 
genus Rhipicentor N. and W. By W. F. Cooper and L. E. 
Robinson 457 
