174 
NATURE 
[ Dee. 9, 1869 
respecting the alleged existence of the rhinoceros in Borneo. 
Mr. R. B. Sharpe exhibited a specimen of Alcedo grandis, a rare 
species of kingfisher from the Terai of Darjeeling. Mr. Andrew 
Murray exhibited specimens of some articles of food sold in the 
markets of Old Calabar. These consisted of examples of a 
frugivorous bat (Pleropus) ready trussed, specimens of a rare 
crustacean (Callianassa tuvnerana), and the larvee of a Longicorn 
beetle found in decayed palm-trees. A letter was read from Mr. 
E. L. Layard, of Cape Town, F.Z.S., containing some remarks 
as to priority of discovery of the remarkable nesting-habits of 
the hornbills. Mr. H. J. Elwes, F.Z.S., exhibited a fine pair of 
horns of the Sinaitic Ibex (Capva nubiana), and Mr. H. E. 
Dresser, F.Z.S., some eggs of the little gull (Larus minutus) 
recently taken in Russia. A communication was read from the 
Rey. O. P. Cambridge, containing notes on some spiders and 
scorpions recently collected in St. Helena by J. C. Melliss, Esq. 
Judging from this collection, which, however, was of small 
extent, the character of the Avaveidea of St. Helena appeared to 
bear a thoroughly European stamp. A communication was read 
from Dr. O. Finsch, C.M.Z S., and Dr. G. Hartlaub, F.M.Z.S., 
on a small collection of birds recently received by the Museum 
Godefroyanum from the Tonga Islands. The species contained 
in this collection were eleven in number, one of which was 
believed to be new to science, and was proposed to be called 
Myiolestes Heinei, A communication was read from Surgeon 
Francis Day, F.Z.S., containing the second portion of his critical 
remarks on the fishes in the Calcutta Museum. Two papers 
were communicated by Mr. J. Brazier, C.M.Z.S., on the localities 
of certain species of land-shells and volutes found in Australia 
-and the neighbouring islands, and on the species of cones met 
with in Port Jackson, N.S.W. Mr. R. B. Sharpe read a paper 
on the birds of Angola collected by J. J. Monteiro, Esq., which 
were accompanied by the notes of the collector. The present 
collection contained twenty-nine species, many of which were of 
great interest. A communication was read from Mr. D. G. 
Elliot, F.Z.S., containing a monograph of the genus Pelecanus. 
The species of pelicans recognised by Mr. Elliot were nine in 
number. Mr. Sclater exhibited a specimen of a new species of 
Mexican wren from the Berlin Museum, which he proposed to 
describe under the name of Zhryothorus nisorius. Mr. Sclater 
also read some notes on the identification of two mammals 
recently described by Dr. Gray from specimens living in the 
Society’s Gardens. A paper was read by Messrs. Sclater and 
Salvin on Peruvian birds collected by Mr. Whitely, being the 
fifth of a series of communications on this subject. Mr. John 
Gould, F.Z.S., exhibited and described a new species of kinghsher 
from North-Western Australia, which he proposed to call Dace/o 
occidentalis. 
London Mathematical Society, November25.— Prof. Hirst, 
and subsequently Prof. Sylvester, V.P., in the chair.—The Rev. 
James White was admitted into the Society, and the Rev. Percival 
Frost proposed for election. Dr. O. Henrici exhibited a model of 
the cubic surface x ys — (#)3 (v + y + 2 —1)® = O, which has three 
biplanar nodes; it was constructed in cardboard to a scale of 24 
inches, as unit. 
z—-1= constant, cut out in cardboard, are connected in a 
horizontal position, and kept at their proper distance by three 
vertical sections y= 2, s=x, «=y, with regard to which the 
surface is symmetrical. The model contains the central part of 
the surface with the three nodes, and is bounded by a sphere of 
8 inches radius, with its centre at the origin, large enough to 
show the position of the three straight lines in the surface (each 
counting for nine), and to give an idea how the surface extends to 
infinity. The interstices between the cardboard are intended to 
be filled up with plaster of Paris, so as to form a solid model. 
Mr. Clifford gave an account of an extension of a theorem of 
Serret’s illustrated by tables, one of which, designated A, is 
annexed, with its explanation. 
| 
Power. Zales 4 5 6 37.118 9 | 10 | 
| 1 We fo be} | 
| | | 
Conic 6 | 8 | 11] 3 | 16] 18 | 21 | 23 | 26 | 
Cubic . —| 10] 12] 15] 19| 21 | 24 | 28 | 30 
Quartic . _ | — | 15] 17] 20| 24 | 29 | 3x | 34 
Quintic - —|— | — | 21 | 23 | 26 | 30] 35 | 41 
Sextic —|—}|—|—| 28 | 30 | 33 | 37 | 42 
Septic |S | Sol | Sed le 36 | 38 | 4t | 45 
Octavic . 5 = | S| | | — | 45 | 47 | 5° 
Nonic « ..« Fila Sa lee Bl ee 
A sufficient number (eleven) of sections «+ | 
The tables, for convenience, refer to points instead of lines, 
and curves of given order instead of curves of given class. The 
meaning of them will best appear from an example. Thus, in the 
Table A above, opposite the word quartic and under the power 8 we 
find the number 29. This means that if the eighth powers of the 
equations of 29 points are connected by a syzygy, the points are 
all on a quartic curve. There are, moreover, intersections of the 
quartic by an octavic, which, in virtue of a theorem of Jacobi’s, is 
an additional piece of information. Mr. Clifford also exhibited a 
second Table B, constructed ina similar manner for surfaces. Mr. 
Roberts made a statement of a theorem in invariants, which, 
however, is so mixed up with other considerations and details, 
that it cannot well be isolated and its limiting circumstances 
explained without going into further details than the limits of this 
notice permit. 
EDINBURGH 
Geological Society, December 2.—Mr. Geikie, F.R.S., 
president, in the chair. The first paper was on the Succes- 
sion of the Laurentian, Cambrian, and Lower Silurian Rocks on 
the Shores of Loch Broom, being a letter addressed to the pre- 
sident by Sir Roderick Murchison. 
Sir Roderick Murchison, in his paper, after alluding to. his 
previous researches in Scottish geology, and especially to the 
order which he had been enabled to establish among the 
rocks of the north-west Highlands, proceeded to give the re- 
sults of a visit which he had paid last summer to the west of 
Ross-shire. Along the shores of Loch Broom he found clear sec- 
tions confirmatory of his previously published views. Among 
the Summer Isles at the mouth of that loch the Laurentian 
gneiss is found with its usual characteristic petrographical cha- 
racter. It throws off the dull red or chocolate-coloured sandstones 
which in one mountain, Ben More, must attain a thickness of 
several thousand feet. These strata are inclined gently towards 
the east, and are overlapped unconformably by the quartz rock 
and limestone which form the lowest portions of the Lower 
Silurian series. From the upper part of the uppermost quartz 
rock there is a perfect ascending passage with the upper flaggy 
gneiss, which rolls eastward over the rest of the Highlands. 
By this fresh appeal to the natural sections of the north-west 
Highlands, Sir Roderick had been again able to confirm the now 
established order of succession among these ancient rocks.— 
Mr. Geikie, F.R.S., afterwards communicated a series of notes 
fora comparison of the volcanic geology of central Scotland with 
that of Auvergne and the Eifel. The author began by alluding 
to the labours of Boué, Forbes, Scrope, Daubeny, and others. 
He then sketched the area occupied by rocks of volcanic origin 
between the Grampians and the silurian uplands of the southern 
counties. The rocks which he proposed to make the subject of 
more special remark in this paper were of carboniferous 
age. 
They were capable, he said, of being broadly treated under two 
groups—tst, plateaux ; and 2d, points of localeruption. 1, Pla- 
teaux of carboniferous volcanic rocks are extensively developed 
in the western part of the midland valley. ‘They form the range 
of the Campsie and Kilpatrick fells, and, crossing the Clyde into 
Renfrewshire, sweep for many miles through the north and 
north-east of Ayrshire. They occur likewise as fragments on 
the Clyde islands, Arran, Bute, and Cumbrae. Extensive as 
the present area of these rocks is, there can be no doubt that 
it once covered a much greater surface, and that one great pla- 
teau of lavas and tuffs stretched from the Ochil Hills to the 
south of Cantyre. Throughout the wide district where the 
rocks still remain they retain a remarkable horizontality. They 
consist of various porphyrites, melaphyres, and tuffs, arranged 
in beds, which are placed over each other with great regu- 
larity. Hence the hillsides wear a terraced appearance from the 
alternation of harder and softer beds. This feature charac- 
terises the Campsie fells and the hills south-westwards to Ar- 
drossan, but it is most conspicuously displayed in some of the 
valleys at the south end of Bute. One of the distinguishing 
features of these plateaux is the comparative infrequency with 
which any vent or true point of eruption can now be 
detected. Occasionally such a vent is found as a boss of 
coarse volcanic agglomerate, or of porphyrite or melaphyre ; but, 
as a rule, all the foci of eruption are now buried under the 
materiais which they emitted. Another feature which runs 
through the plateaux is the apparent continuity of the several 
beds. Viewed from a little distance, the terraces of trap seem 
each perfectly continuous for long distances. A closer exami- 
