368 
NATURE 
| Fed. 3; 1870 
the neighbouring Australians, but were allied by black skin and 
woolly hair to the distant Africans, while they were assimilated 
by resemblance of language, customs, and habits of thought to 
many races scattered over vast areas. The author sought to 
explain this relation by constructing an ideal southern continent, 
whence all the dark-coloured races surrounding the Indian 
Ocean, and extending into the Pacific and Southern Oceans, may 
have radiated. He regards the Tasmanian as probably older 
than the Australian. Dr. Hooker, whose authority had fre- 
quently been quoted in the paper, pointed out the similarity 
and differences that obtain between the floras of Australia, Tas- 
mania, New Zealand, South Africa, &c. It has recently been found 
that the flora of the Howe Islands is very unlike that of Australia, 
although so near to the coast. He protested, however, against 
the inference that the line of migration followed by plants is 
necessarily the same as that pursued by the higher animals, 
The President alluded to the great difference between the Aus- 
tralian and Tasmanian, especially in the character of the hair, 
and he regarded it as physically impossible that the Tasmanian 
could have come from Australia. He suggested that an inter- 
rupted communication, by a chain of islands, may have extended 
from New Caledonia to Tasmania, similar to that which now 
connects New Caledonia with New Guinea ; and that by this 
means a low negrito type may have spread eastwards over this 
area.—Mr. Howorth’s paper, ‘‘On a frontier-line of Ethnology 
and Geology,” was then read. Siberia and North America 
form a well-defined province, botanically, zoologically, and eth- 
nologically. North of the isothermal line forming the southern 
boundary of this province dwell the Ugrian races, whose conditions 
of existence were compared by the author with those of the pre- 
historic period. In Europe the isothermals have been gradually 
twisted to the north by the Gulf Stream; and the author believes 
that the gradual advent of the stream may be traced from no 
earlier period than about the twelfth century B.c. ; Remarks on 
this paper were made by the President, Dr. Hyde Clarke, Dr. 
Richard King, and Colonel Lane Fox.—Mr. Atkinson read a 
**Note on the Nicobar Islands,’’ and exhibited some grotesque 
figures carved in wood, taken from the Nicobars by Capt. Edge 
in 1867, and recently brought to this country by Capt. Mackenzie. 
These figures are to be placed in the Christy collection, and similar 
objects have been forwarded to the Museum in Edinburgh, 
London Mathematical Society, January 13.—Prof. Cayley, 
president, in the chair. Mr. Walker gave an account of a paper 
**On the Equations of Centres and Foci of, and Conditions for, 
certain Inyolutions.” In this communication it is shown that 
the three points corresponding to one having an assigned distance 
(a’) from the origin, in one of three involutions determined by a 
quartic, and found from the equation— 
(abcd ¥ x/,1)°, (bcde X x’, 1)3, (cdef X x',1)°, (defy € x’, 1)3, (x, 1)? =0, 
the sextic covariant of the quartic being written (ab cdefg¥ xy), 
This form has been arrived at in carrying-out a suggestion of the 
president, Prof. Cayley. It contains the equations giving the 
three centres of the involutions determined by the quartic, as 
well as that giving the six double points (the geometrical signi- 
ficance of which latter equation has been already pointed out by 
Dr. Salmon), by making 2’ infinitely great, and equal to x, 
successively. The case of the quartic breaking up into two 
quadratics is next discussed, when the roots of one correspond 
respectively to those of the other. The condition for two cubics 
(wv) determining an involution, of such a kind that the three 
roots of one correspond each toa root of the other, is investigated. 
This has (since the meeting) been identified by the author with 
A 6”"- a'S2=0, A,A’, being discriminants of # and z, 
while 6S’ are the co-efficients of A and A® respectively in the 
discriminant of «+Av. The equations for determining the 
centre and double points—or, more generally, that determining 
the point corresponding to an assigned one—in the involution 
determined by two cubics, satisfying the above condition, are 
also investigated. Dr. Ilenrici, Prof. Hirst, Mr. Clifford, and 
the President took part ina discussion on the paper. The Presi- 
dent then made a statement of some results he had arrived at 
with reference to quartic surfaces. Mr. Roberts exhibited and 
explained diagrams of the pedals of conic sections which he had 
constructed by the methods described in his paper read before 
the society, January 14th, 1869. 
Quekett Microscopical Club, January 28.—P. Le 
Neve Foster, Esq., president, in the chair.—A paper was 
read by Dr. Robert Braithwaite on the geographical distribution 
of mosses, The paper gave an abstract of the arrangement pro- 
posed by Prof. Schimper, who divides the whole of Europe into 
three areas in latitude—viz. (1), a northern zone, comprising 
N. Russia, Scandinavia, and N. Scotland ; (2), a middle zone, 
extending south of this to the foot of the Alps, and including all 
central Europe ; (3), a southern zone, reaching from the last to 
the Mediterranean. More important than these is their distri- 
bution in altitude, or height above the sea level, and for this five 
regions are indicated, each characterised by certain predominant 
species, and marked out by lines gradually falling in altitude as 
we pass northward to the pole, where the extreme limits, or that 
of the sea level and the line of perpetual snow, become co- 
incident. Commencing at the sea level, the dimensions in alti- 
tude are—(1), the Campestral region, or that of the cultivated 
field and fruit trees, embracing the greatest varieties of soil and 
conditions of surface; (2), the Montane, or lower mountain 
region, marked at its upper limit by the disappearance of the 
beech ; (3), the Sub-Alpine region, extending from the upper 
limit of the beech to the upper limit of the spruce fir; (4), the 
Alpine region, embraced between the commencement and termi- 
nation of growth of the dwarf pine, and marked by the presence 
of dwarf birch ; (5), the Supra-Alpine region, reaching aboye 
the limit of the trees named to the line of perpetual snow. A 
brief sketch was then given of the various /aditats affected by 
mosses, and lists of the characteristic species given; these em- 
braced the dwellers on walls, roofs, trees, heaths, bogs, and 
rocks. They were illustrated by a fine series of specimens of 
mosses and their associated flowering plants, prepared by the 
late Mr. N. B. Ward, who thus ingeniously attempted to work 
out the idea of representing the whole flora of a locality at one 
glance. Conspicuous among these were the sheets from Ben 
Lawers, Ben Voirlich, Heidelberg, Killarney, and Eridge 
Rocks. 
Anthropological Society, January 18.— Annual General 
Meeting.—John Beddoe, Esq., M.D., president, in the chair. 
The report of the auditors showed the income of the society in 
1869 to have been 1,091/. gs. 5d., the expenditure 964/. 9s. 8d., 
and the balance in hand on the 31st December 126/. 19s. 9d. 
The report of the council was read and adopted. The president 
then delivered the annual address, including a full obituary 
notice of Dr. James Hunt, founder of the society. The ballot 
for the election of officers and council to serve in 1870 was taken 
with the following result :—President, John Beddoe, M.D.; vice- 
presidents, H. Beigel, M.D., Captain R. F. Burton, Dr. Char- 
nock, J. Barnard Davis, M.D., F.R.S., Captain Bedford Pim, 
R.N., Dr. Berthold Seemann ; director, Thos. Bendyshe, M.A.; 
treasurer, Rey. Dunbar I. Heath, M.A.; council, J. Gould Avery, 
J. Burford Carlill, M.D., S, E. Collingwood, Walter C. Dendy, 
George Harris, Jonathan Hutchinson, W. B. Kesteven, Kelburne 
King, M.D., Richard King, M.D., A. L. Lewis, St. George J. 
Mivart, F.R.S., Major S. R. I. Owen, Edward Peacock, F.S.A., 
J. Spence Ramskill, M.D., C. Robert Des Ruffieres, John 
Thurnam, M.D., W. S. W. Vaux, F.R.S., C. Staniland Wake, 
Alfred Wiltshire, M.D,, E. Villin. 
Entomological Society, January 24. — Annual General 
Meeting, Mr. Frederick Smith, vice-president, in the chair. 
The Report of the Council for 1869, and an address by Mr. H. 
W. Bates, the retiring president, were read. The following 
thirteen members were chosen to form the council for 1870, viz: 
Messrs. Bates, Dallas, Dunning, Fry, Grut, M‘Lachlan, Parry, 
Pascoe, Saunders, Stevens, Wallace, and Wormald. Mr. Alfred 
Russell Wallace was elected president for 1870; and the 
following officers were re-elected :—Mr. Stevens, treasurer ; 
Messrs. Dunning and M‘Lachlan, secretaries; Mr. Janson, 
librarian. The thanks of the society were voted to the officers 
and members of the council for their services during the previous 
year. 
GLAscow 
Philosophical Society of Glasgow, January 12.—Dr. 
Francis H. Thomson, vice-president, in thé chair. The presi- 
dent, Dr. James Bryce, F.G.S., gave an account of the “ Geo- 
logical Structure of Skye and the West Highlands.” The 
difficulty and danger of thoroughly studying the peculiar geolo- 
gical structure of Skye were so great that no geologist, in the 
author’s opinion, should undertake it without the company of 
an associate; and as he considered that no such person should 
ascend the mountains for the first time unaccompanied, the 
author specially recommended Angus Nicholson as a reliable 
guide. Dr. Bryce dwelt at some length upon the wonderful 
peculiarities in the structure of the Cuchullin mountains, which 
