404 Scientific Intelligence. 
a rough, dark clay bed (A), containing nodules that are like the 
serpentine nodules in form, size and position, but which consist of 
indurated clay, reddish gray or grayish yellow in color. From the 
unaltered clayey nodules there is a gradual passage, through others 
partly altered, to those consisting wholly of serpentine. ~D’Achi- 
ardi concludes that the serpentine nodules were produced through 
the alterations of the clay nodules. e refers their formation to 
the sine of hot magnesian waters ona hy ated aluminous silicate, 
and the replacement thereby of the alumina by magnesia. The 
halhoyaibe like material he regards as cakaoine the alumina 
ich was removed from the nodules in the process of alteration. 
10. On the formation of Mountains and the hypothesis of a 
liquid substratum beneath the Earth’s crust ; by Rev. O. Fisuer, 
(Proce. Cambridge Phil. Soc., Feb. 22.)— This paper was a sequel to 
one read in Dec, ~ 3, in which it had been compe that, upon oe 
formed by cual’ of its volume through faling; they are to0 
oli 
great to be so accounted for if the earth h oled a solid 
bo In the present communication it was therefore assumed 
that there is a iguid layer beneath the cooled crust; an a 
d 
proximate calculation was made of the form which the corrugations 
of a flexible crust would take if so supported. It was shown that 
their lower surface would consist of a series of equal circular ares 
arranged in a festoon-like manner, and having a radius 2H, where 
p, & are the — of the crust and liquid Ader eras “awd e the 
thickness of the crust. It was argued that the cor oC of 
this form of comigation agree fairly well with som th e- 
nomena of mountain elevation, but that it does not ‘stiffice to ex- 
oie lau bastie nd the continental plateaux.— Nature, 
arch 18 
. Botany of the Island of Amsterdam.—It is a curious fact 
that the little island of Amsterdam, in the South Indian Ocean, is 
known to be covered with trees, whilst the island of St. Paul’s, 
only fifty miles to the south, is destitute of even a shrub, Botanists 
have long been anxious to ‘determine the character of the Amster- 
dam forest; but the difficulty of effecting a landing on the — 
has generally prevented the collection of specimens. In the last 
part of the Jowrnal of the Linnean Society, Dr. Hooker announces 
that at length he vd received the de sired 5 specimens, these having 
been collected b mmodore _— be who states that they 
represent the or ae as cies of tree gro on the island. Dr. 
Hooker identities this with the Phytica psorss of Thouars, a tree 
Amphioxus lanceolatus.—Prof. i Hux sley has bown, - a paper 
ae before the Royal Society (Ann. Mag. Nat. Hist , 1V, xv, 225), 
