Fan. 26, 1871] 

SOCIETIES AND ACADEMIES 
LONDON 
Zoological Society, January 17.—Prof. Newton, F.R.S., 
V.P., in the chair. The Secretary read a report on the addi- 
tions to the Society’s menagerie during the month of December 
1870, amongst which were particularly noticed a specimen of the 
Two-toed Amphiuma (4A mfphiuma didactylum), and an example 
of Erxleben’s Monkey (Cercopithecus Erxlebent). On concluding 
his report the Secretary called attention to the registers of acces- 
sions to and deaths in the Society’s menagerie, which lay on the 
table, and showed, in contradiction to statements recently pub- 
lished by Dr. Gray, that they were faithfully kept up, and that a 
revised abstract of the former was published every year as an 
appendix to the Society’s ‘‘ Proceedings.” —Mr. Howard Saun- 
ders exhibited and made remarks on a series of skins of eagles 
belonging to Aguila imperialts, A. bifasciata, and A. nevioides.— 
A letter from Mr. R. Brown was read, recommending the intro- 
duction of hogs into countries where poisonous serpents were 
frequent, in reference to a communication from the Governor of 
Santa Lucia, read at the last meeting of the Society. —Mr. Jules 
Verreaux made some remarks on the facility with which the 
colouring matter in the wings of the Touracous was soluble, and 
stated that he had observed it washed out in the living birds by 
heavy rain.—Mr. J. E. Harting exhibited and made remarks on 
a specimen of Sabine’s Snipe, recently killed in Ireland.—Mr. 
Sclater made some remarks on the amphibians usually called 
Axolotls, now living in the Society’s gardens, and pointed out 
that if what Prof. Baird had recently stated were correct, these 
were not the true Axolotl of the lakes of Mexico (Sivedon 
mexicanum), but the larval form of a known Salamander— 
Amblystoma mavortium, Baird. Mr. Sclater likewise exhibited 
a typical specimen of Aéeles variegatus, Wagner, and pointed 
out its unquestionable identity with 4. Bartlettz, Gray.—Mr. J. 
W. Clark read a paper on a fine skull of the Narwhal (Monodon 
monoceros) with two tusks in the Cambridge University Museum, 
to which were added full particulars as to all the known bidentate 
skulls of this animal.—A paper was read by Dr. J. C. Cox, 
C.M.Z.S., containing descriptions of some new species of Aus- 
tralian land-shells.—Prof. Newton exhibited and made remarks 
on some new and rare birds’ eggs, amongst which were those of 
the Sanderling (Ca/:dris arenaria) and Lesser Sheath-bill (Chionis 
minor).—Mr. St. George Mivart pointed out the characters of a 
new genus of Insectivorous Mammals proposed to be called 
Hemicentetes, founded on the Zyrinaceus madagascariensis of 
Shaw, to which was added a revised synopsis of the known 
genera of the order Insectivora.—A communication was read 
from Mr. A. G. Butler, containing descriptions of some new species 
of Exotic Lepidoptera.—Mr. G. F. Angas communicatad a list 
of additional species of marine mollusca to be included in the 
Fauna of Port Jackson and the adjacent coasts of New South 
Wales.—Mr. Sclater read some notes on the typical specimens 
of Zyrannula mexicana, Kaup, and 7: barbirostris, Swainson.— 
A second communication from Mr. Sclater contained remarks on 
certain species of Demdrocolaptide, in the collection of the Smith- 
sonian Institution. 
Geological Society of London, January 11.—Joseph 
Prestwich, F.R.S., President, in the chair. The follow- 
ing communications were read :—1. ‘‘On the older Metamorphic 
Rocks. and Granite of Banffshire,’ by T. F. Jamieson, 
F.G.S. The author indicated three divisions in the meta- 
morphic strata a Banffshire :—At bottom of great thickness of 
arenaceous beds, more or less altered into quartz-rock, gneiss, 
and mica-schist ; next a series of fine-grained clay-slates, in the 
midst of which is a bed of limestone ; and then again an upper 
group of arenaceous strata. The author stated that the arrange- 
ment of the rocks is very similar to that occurring in Bute and 
Argylesbire. He remarked that the general texture of the beds 
is fine-grained, and considered that they were probably deposited 
in the depths of the sea, off the mouth of a great river, the 
deposition of the argillaceous strata having taken place during a 
period of increased depression. The deposition of the beds was 
said to have probably taken place after the formation of the 
(Cambrian) Red Sandstone and Conglomerate of the North-west 
Highlands, or in Lower Silurian times, the river by which the 
sediment was brought down being supposed to have drained the 
great Laurentian region to the north-west. After their accumu- 
lation the author supposed that ‘‘a glow of heat from beneath” 
approached them, causing expansion and the wrinkling of the 
mass into folds running from S.W. to N.E. The granites were 
NATURE 
259 


considered by the author to owe their origin to the fusion and 
recrystallisation of the arenaceous beds. Prof. Ramsay 
observed that the general section wonderfully corresponded with 
that given many years ago by Sir Roderick Murchison, of the 
Silurian and Laurentian rocks at Cape Wrath, and it seemed to 
him that the large views originally propounded by Sir Roderick 
were confirmed by the author. He was glad that the meta- 
morphic origin of granite was supported by Mr. Jamieson, as he 
had held that view for several years, and he was pleased to find 
that opinions which had formerly met with so many opponents 
were constantly gaining acceptance. The fusion of these sedi- 
mentary rocks by metamorphic action was not identical with the 
fusion of lava, but their fluidity might be the same ; and if that 
were the case there could be no difficulty in accepting the possi- 
bility of the injection of such fused rocks into crevices and 
fissures. The crumpling of the beds, however, was due to more 
extensive causes than those contemplated by the author. The 
proportion of igneous rock injected into contorted rocks, like 
those of North Wales, was almost infinitesimal, and the 
crumpling could hardly be due to mere local causes.—Prof. 
Ansted referred to what he had observed in the north-west part 
of Corsica, where about 4oft. of granite were distinctly inter- 
stratified between perfectly unmetamorphosed beds of sandstone 
and limestone, without any alteration at the points of contact, 
such as would be produced by an igneous rock. He also cited 
the crumpled strata in the Maritime Alps, in which the granites 
were parallel with the other beds, and seemed to form part of 
them. Mr. Carruthers mentioned that the late Prof. Fleming 
twenty years ago had taught the same doctrine as to the nature 
of granite as that held by the last speakers.—Mr. David Forbes 
agreed that the crumpling of the stratawas not due to the in- 
trusion of any eruptive rock. He completely disagreed with 
Prof. Ramsay and the author as to the origin of granite, and 
maintained that, in the sedimentary rocks traversed by the 
granite, the requisite ingredients for the formation of granite did 
not exist. The proportion of felspar in quartzose rocks was 
infinitesimally small, as compared with that entering into the 
composition of granite. He could not accept the notion of the 
heat from the interior approaching gradually to some portion of 
the surface. Prof. Ramsay, in reply to Mr. Forbes, maintained 
that some of the slaty rocks of Wales, by extreme metamor- 
phism, would pass into some kinds of granite. As to the con- 
ditions of metamorphism of the rocks, this process must have 
gone on at a time when these older rocks were oyerlain by a great 
thickness of more recent beds which have since been removed by 
denudation. 2. ‘On the connection of Volcanic action with 
changes ot Level,” by Joseph John Murphy, F.G.S. 
The author commenced by discussing the chemical theory of 
volcanic action, which he considered he had disproved. He 
remarked on the coincidence of volcanic action with elevation 
of the surface, but stated his opinion that the elevation of one 
part of the earth’s surface and the depression of another, are 
the results of a movement of subsidence in the following 
manner :—The interior of the earth is constantly cooling, and 
as it cools it must contract. But the cold strata of the surface 
cannot contract in the same proportion; and as they must 
remain in contact with the core, they are compelled to 
form folds and ridges. The breaking out of volcanoes is due to 
the breaking of part of the earth’s crust by these foldings. 
According to the author, ‘‘ volcanic action is not the cause, but 
the effect of secular changes of level; and secular changes of 
level are due to the subsidence of the surface on the interior, as 
the interior contracts in cooling.” 3. ‘*On some points in the 
Geology of the neighbourhood of Malaga,” by Don M. de 
Orueba. Communicated by Sir R. I. Murchison, F.R.S., F.G.S. 
After referring to the writings of previous authors upon the geo- 
logy of the south of Spain, the author noticed a mountain-chain 
near Antequera, one branch of which, known as the ‘‘ Torcal,”’ 
he described as presenting a very singular appearance from the 
huge blocks of stone of which it is composed. The division of 
the rock into separate blocks, often of the most fantastic shapes, 
was attributed by the author to denudation by water. The 
“ Torcal” consists of a compact limestone, generally of a red 
colour, resting conformably on the east upon a fine-grained white 
oolitic marble of considerable thickness. At the divisional line 
between the two formations many Ammonites were said to occur, 
and three of these were doubtfully identified with 4. giganteus, 
biplex, and annulatus, These species would indicate the deposit: 
to be probably of Portlandian age. The plain of Antequera was 
considered by the author to consist of Tertiary formations. One 
of these, at the south of the city, he regarded as analogous to the 
