iv 
Contents. 
PAGK 
The Granite Area op the Schapenberg, Somerset West. 
(From the Greological Department, South African College.) By 
A. R. E. Walker. (With Map ; text-fig. 1.) . . . . 193 
Radial Lines in Rontgen Interference Patterns. By J. Steph. 
VAN DER LiNGEN ......... 203 
Note on Protective Resemblance, Etc., in Post-Larval Stages 
OP Some Cape Fishes. By J. D. E. Gtilchrist, M.A., D.Sc, 
Ph.D. ... ."^ ....... 205 
Note on Polysaccum crassijpes, D.C. : A Common Fungus in Euca- 
lyptus Plantations round Pretoria. By Paul A. van der 
BiJL, M.A., F.L.S., Mycologist, Union Department of Agriculture. 
(With Plates XXXIII— XXXYIII) 209 
Heart Rot of Ptmroxylon utile (Sneezewood) Caused by Fames 
rimosus (Berk). By Paul A. van der Bul, D.Sc, F.L.S., 
Mycologist, Department of Agriculture, Union of South Africa. 
(With Plates XXXIX— XLIV) 215 
The Electro-Motive Changes accompanying Activity in the 
Mammalian Ureter. By W. A. Jolly. (From the Physiology 
Laboratory, South African College.) . . . . . .227 
On Some Stages in the Life History op C-netum. By H. H. W. 
Pearson, Sc.D., F.R.S., and Mary R. H. Thomson, B.A. 
(With Plates XLV— L) 231 
The Theory op Automatic Regulators. By H. Bohle . . 271 
On Hybrid Forms in the G-enus Satyrium, with Descriptions 
OP Two New Forms. By A. V. Duthie. (With Plates LI — 
LIII) . . . . ^ 289 
Note on the Occurrence op Daphnin in the Arthrosolen. By 
M. Rindl. (From the Chemical Laboratory of the Grey Univer- 
sity College, Bloemfontein) ........ 295 
African Myxomycetes. By A. Y. Duthie ..... 297 
Ionization of Gases and the Absorption of Rontgen Rays. By 
Lewis Simons, B.C. (Lond. and Cape), Lecturer in Physics, 
Victoria College, Stellenbosch, South Africa . . . .311 
Note on Palmstr0m's Generalisation of Lame's Equation. By 
Sir Thomas Muir, LL.D 323 
