270 
Union of South Africa. The first paper, by Dr. 
Ernest Warren, describes infection experiments with 
a species of cochineal insect (Green’s Coccus cacti, 
var. ceylonicus) which showed that, of the two species 
of prickly pear common in South Africa, the long- 
spined Opuntia monocantha and the small-spined O. 
tuna, only the former succumbed to the attack of the 
insect, some substance probably being present in the 
sap of the latter which is injurious to the cochineal 
insect, since even a wounded surface is not attacked. 
The second paper, derived from the Queenslander, 
describes a method introduced by Mr. O. C. Roberts, 
in which treatment consists in the action of arsenious 
trichloride vapour, at the rate of three quarts of the 
compound per acre of bush, Up to the present this 
has only been tested on several hundred acres of land, 
but the results are said to be sufficiently promising to 
warrant much more extensive operations in the near 
future. 
Stupents of palaobotany will note with pleasure a 
folio memoir in German on certain fossil calcareous 
algae from Japan and China, by Dr. H. Yabe (Sci. 
Rep. Tohoku Imp. University, Sendai, Japan, vol. i., 
No. 1). Only three species are described, but two 
represent new genera, Metasolenopora and Petro- 
phyton, and the author’s well-known care in micro- 
scopic details leads to their adequate illustration. 
UnpER the title of ‘‘Les plus jeunes volcans de la 
France,’”’ Prof. Glangeaud, of Clermont-Ferrand, con- 
tributes a well-illustrated account of the chain of the 
Puys to the Revue générale des Sciences, 25° Année 
(1914), p- 50. The trachytic domes, which are more 
common in the Mont-d’Or region, are compared with 
those of the Montagne Pelée and Guadeloupe. Reyer’s 
descriptions of those in Bohemia may provide, how- 
ever, examples nearer home. A remarkable amount 
of modern information, including an explanation of 
the puzzling Puy Chopine, is compressed into this 
single article. 
In vol. xx. of the Bevichte der naturforschenden 
Gesellschaft zu Freiburg-im-Breisgau (1913), W. 
Deecke discusses the frequent variation in type to be 
found in European sedimentary rocks of all ages, and 
concludes that deep marine basins and shallow waters 
lay side by side, and that the European area always 
showed, as now, an interlocking of sea and land. 
Continuous oceanic deposits seem wanting, and the 
acceptance of this view helps to account for the near 
association of different sedimentary facies, which other 
writers have ascribed to the importation of one type 
over another during lateral thrusting. It may be 
noted that the author regards the fucoids of the Alpine 
Flysch, not as alga or worm-tubes (see NATURE, 
vol. Ixxxv., p. 284), but as sponge-bodies indicative 
of deep water. In a later paper on ‘‘ Die Bedeutung 
salzfiahrender Schichten ftir tektonische Vorgange,”’ 
Deecke ascribes the anomalous position of some of the 
Alpine masses to gravitational slipping over Triassic 
strata, from which solution has removed sulphates and 
chlorides. Such solution takes place easily when the 
beds are lifted above the usual water-table and are 
exposed to free percolation, and the author asks for 
caution before the faulted relation of any overlying 
NO; 2324, WOL..93)| 
NATURE 
[May 14, 1914 
mass to its support is ascribed to overthrusting from 
a distant source. It will be seen that these two 
papers have a common philosophic aim. 
Tue Rev. H. V. Gill has sent us a reprint of his 
paper read at the last meeting of the British Associa- 
tion on the distribution of large earthquakes in time, 
and space. Mr. Gill’s theory is that a great mass- 
| displacement of the crust, such as occurs during a 
violent earthquake, gives rise to a “‘wobble”’ or un- 
evenness in the rotation of the earth, which is 
neutralised by other mass-displacements occurring 
either in a distant region or regions symmetrically 
placed along the great circle through the origin, or 
of displacements in the opposite direction in the neigh- 
bourhood of the origin. To test this view, he has 
examined the distribution of the 889 world-shaking 
earthquakes recorded by the seismological committee 
of the British Association. He finds that 674 (or three 
out of every four) great earthquakes occurred in 
groups, successive members of which were separated 
by a week or less, while the remaining 215 were 
isolated disturbances. Of the former, 163 (or 18-6 per 
cent. of the whole) belonged to groups of two or more 
earthquakes occurring at different places symmetric- 
ally situated with reference to the origin of the first 
earthquake of a group; 511 (or 57-1 per cent.) were 
members of groups occurring at or near the same 
place. No attempt, however, is made to show that 
the displacements of individual groups of the latter 
class occurred in opposite directions. 
THE annual report of the Hampstead Scientific 
Society for 1913 naturally refers with gratification 
to the favourable reception which was accorded to 
the publication, ‘‘ Hampstead Heath: its Geology and 
Natural History.’’ The membership of. the society 
has attained a ‘record figure”’ of 374, with a net 
increase of thirty for the year. The report contains 
brief notices of the many valuable papers which have 
been read to the society, and a summary of the 
meteorological statistics for the Hampstead Observa- 
tory for 1913. ‘‘The combination of meteorological 
circumstances in July was most unusual; coupled with 
a remarkable cloudiness of eighty-two and an ex- 
tremely deficient sunshine of only 109 hours were a 
mean pressure of 30-087 in.—a figure some way in 
excess of the average—and a rainfall an eighth of an 
inch below the normal, falling on only eleven days.” 
For the first time, average meteorological data are 
included in the report; this action marks the fact 
that the station has been at work for five years. From 
these preliminary averages it would appear that 
Hampstead is the coldest, rainiest, snowiest, and 
frostiest, as well as almost the sunniest and foggiest 
of the stations in the neighbourhood of London. 
THE report of the Royal Prussian Meteorological 
Institute for the year-igt3 (director, Prof. G. 
Hellmann) exhibits great activity in useful work, 
relating chiefly to land meteorology and special re- 
searches. Arrangements have been made for the pre- 
paration of an important work on the climate of 
Germany, and a special department has been created 
for the purpose. Among the researches made at the 
Potsdam Observatory may be mentioned the compari- 
son of different sunshine recorders, and the investiga- 
