
ApRIL 7, 1923] 
to the appointment of a successor to take up office , 
in October, 
Prof. G. H. Thomson, professor of education, and 
joint author with Dr. William Brown of the “ Essen- 
tials of Mental Measurement,”’ has been invited by 
the Teachers’ College, Columbia University, New 
York, to spend next academic year there, delivering 
advanced courses on psychology. The council of 
Armstrong College has granted him a year’s leave for 
this purpose. 
__ Lonpon.—Presentation Day will be held in the 
_ Royal Albert Hall, on Thursday, May 3. 
he degree of D.Sc. in biochemistry has been con- 
ferred on Miss K. H. Coward, an internal student, of 
University College, for a thesis entitled ‘‘ The Forma- 
tion of Vitamin A in Plant Tissues.”’ 
Applications are invited for the Astor chair of pure 
mathematics tenable at University College, in succes- 
_ sion to Prof. M. J. M. Hill, retired. The latest date 
for the receipt of applications, by the Academic 
_ Registrar, University of London, South Kensington, 
S.W.7 (12 from each candidate) is May 24. 
MANCHESTER.—The trustees of the Dickinson 
scholarships, open to medical students and graduates 
of the University, have announced the conditions and 
regulations. The scholarships are as follows: (i.) 
research travelling scholarship in medicine, of the 
_ value of 300/. for one year, awarded annually; the 
scholar is required to spend at least ten months abroad 
and undertake there original investigation; (ii.) 
anatomy scholarship (25/. for one year), to be awarded 
to the most distinguished first-year anatomy student ; 
‘(iii.) surgery scholarship (75/. for one year, offered in 
alternate years to a scholarship in pathology), open to 
medical graduates of the University; the scholar 
must devote himself to original investigation ; and 
(iv.) pathology scholarship (75/. for one year), on the 
same lines as the surgery scholarship. Full particu- 
lars are to be obtained from Mr. Frank G. Hazell, 
Secretary to the Dickinson Trustees, The Royal 
Infirmary, Manchester. 
Oxrorp.—A fund amounting to nearly 2000/, has 
been raised to provide a memorial of the late Sir 
William Osler, Kegius professor of medicine. It has 
been decided to place a memorial bronze plaque in 
the University Museum, and to award a medal every 
five years to a graduate of the University who has 
made some distinguished contribution to medical 
science. It is also desired to provide a fund to assist ° 
teachers in the University to travel for purposes con- 
nected with medical knowledge and research. For 
this latter object further contributions are required ; 
these should be sent to Mr. A. P. Dodds-Parker, 
2 Holywell, Oxford. 
_ The professor of pathology, Dr. G. Dreyer, has been 
appointed to represent the University at the forth- 
coming celebration at Paris and Strasbourg of the 
centenary of the birth of Pasteur. 
Mr. M. E. Shaw, of New College, has been elected 
Radcliffe travelling fellow. The Radcliffe prize has 
been awarded to Dr. A. D. Gardner, University Col- 
lege, sometime Radcliffe travelling fellow. 
he Matteucci gold medal, conferred as a posthum- 
ous honour by the International Research Council at 
Brussels in 1919 on the late Mr. H. G. Moseley, of 
Trinity College, has been received at Oxford and 
delivered to his mother, Mrs. Sollas. 
The governing body of Exeter College will hold an 
election in the summer term to a research fellowship 
of 200/. a year, free of income tax, tenable for 5 
years. Candidates, who must be members of the 
University of Oxford of at least B.A. standing, must 
send in applications by May 15 to the rector, who will 
supply further details. 
NO. 2788, voL. 111] 
NATURE 
Societies and Academies. 
LonpDoN. 
Geological Society, February 16.—Prof. A.C. Seward, 
president, in the chair.—A. C. Seward: The earlier 
records of plant-life (presidential address). Refer- 
ence was made to the views of Dr. Church on the 
origin of life in the waters of a primeval world-ocean, 
and on the origin of terrestrial vegetation from highly- 
organised Alge transferred by emergence of portions 
of the earth’s crust above the surface of the water. 
The vegetation of the land may have received addi- 
tions from upraised portions of the crust at more 
than one epoch in the history of the earth. The 
course of evolution is probably more correctly illus- 
trated by the conception of separate lines of develop- 
ment, than by that of a branching tree implying the 
common origin of the main groups of plants. The 
unfolding of plant-life must be considered in relation 
to the changing geological background. Diffusion- 
phenomena, as illustrated by the so-called Liesegang 
figures, possibly explain the origin of some of the 
structures which are usually attributed to organic 
agency. We have no knowledge of any Pre-Cambrian 
land-flora. The phyla of Lycopods and Ferns are 
regarded as independently-evolved groups. The wide 
geographical range of Archeopteris was emphasised, 
and reference was made to the difficult problems 
1aised by the occurrerce of Upper Devonian floras 
well within the Arctic circle, at least equal (in the 
variety of the plants and in the vigorous developmeat 
of the vegetation) to the more southern floras of 
Ireland, Belgium, and other regions. 
March 14.—Prof. A. C. Seward, president, in the 
chair.—E. M. Anderson: The geology of the schists of 
the Schichallion district of Perthshire. Between Carn 
Mairg and Schichallion the succession is :—graphite- 
schist: pebbly quartzite: mica-schist: non-pebbly 
quartzite : schichallion boulder-bed. Following the 
boulder-bed, and thus on the same side of the quartzite, 
are a white limestone, a banded series of siliceous and 
micaceous rocks, a grey carbonaceous limestone, and a 
slightly carbonaceous mica-schist, which may be named 
the grey schist. On approach to the white limestone 
the boulder-bed becomes highly calcareous. This 
conglomerate is probably a tillite, and has been 
partly formed from the material of the limestone. 
There may thus be a chronological sequence, of which 
the oldest visible member is the grey schist, extending 
upwards to the Ben Ledi grits in an adjoining part 
of Perthshire. In the northern part of the Schichallion 
district the Dalradian series is bordered by the 
Struan flags. The junction is probably not an 
unconformity, but either a normal fault which has 
been affected by strong, horizontal movement, or 
else a folded thrust.—H. H. Read: The petrology 
of the Arnage district in Aberdeenshire: a study 
of assimilation. The modification of magmas by 
the incorporation of material of sedimentary origin 
is here termed contamination. In the Arnage mass 
in Aberdeenshire the sediments concerned in con- 
tamination are: (a) andalusite-schists and pebbly 
grits of the Fyvie series ; and (b) biotite-schists and 
subordinate hornblende-schists of the Ellon series. 
The contaminated rocks occur as a roof-zone, some 
hundreds of feet thick, overlying a sheet of norite 
rich in magnesia, and are of four types. Assuming 
that the initial magma was normal gabbro, the 
contamination-process depends on reciprocal reaction 
between initial magma and xenoliths, whereby the 
magma loses magnesia and lime and becomes richer 
in alumina and alkalies, the final results of the 
reciprocal reaction being the granitic Ardlethen 
