730 General Notes. 
ous series of the west and southwest shores of Spitzbergen is over 
200 m. in thickness, and is divided by Dr. Nathorst into the Ursa 
Sandstone, regarded as Devonian, the Cyathophyllum Limestone, 
the Spirifer Limestone, and the Productus Chert. This series is 
not followed by grits, sandstones, and coal-measures, but by shales, 
marls, and sandstones containing an exclusively Permian fauna, an 
the series itself, though as a whole regarded as stratigraphically 
equivalent to the Carboniferous Limestone, contains a certain 
mixture of Permian fossils. The Productus-chert consists of beds 
of chert composed largely of disintegrated siliceous sponges, but 
rich also in Producti and other calcareous fossils, and of intercalate 
siliceous beds consisting of minute grains of quartz, but rich in 
sponge spicules. The cherty rocks, unlike those of Yorkshire and 
North Wales, have yielded entire forms of sponges, which have 
been described by Dr. E. von Dunikowski. 
Dr. R. H. Traquair (Geol. Mag., 1888, pp. 251-254) describes 
three new species of Palzeoniscide from the English Coal-Measures. 
The article is the second contribution from Dr. Traquair upon this 
subject, the first being contained in the December issue of the same 
magazine for the year 1886. 
In the July issue of the Geological Magazine Mr. A. C. Seward 
comes to the support of Prof. Williamson’s remark that the specific 
names and definitions of Calamites are probably worthless, bie 
figure and description of a specimen which upon one side shows P e 
characters of C. undulatus, while the other side of the same cylinder 
has narrow and equal ribs. 
Dr. Schweinfurth has discovered Lower Carboniferous a af 
the Arabah valley of Upper Egypt, opening out into the Gul ne 
Suez. He recognizes the identity of the beds he describes wit 
those of the Wadi Nasb in the Sinaitic Peninsula; the genera are In 
most cases identical, and the species characteristically Carboniferous. 
Mesozo1c.—Of the lower portions of the Mesozoic serios oot 
the Rhaetic and Liassic strata are developed in Sweden, p si 
more than twenty-four species are enumerated by Prof. meee 
from the formet and 129 from the latter group. There = hisha 
wide gap in the middle portion of the Mesozoic, until the raii 
members of the Cretaceous are reached. These are highly 
iferous, the list comprising 456 species. 
Jurassic.—Mr. R. Lydekker (Geol. Mag., 1888, p. 309) ger 
the genera of Ichthyopterygia to three, viz.: Ophtha n j 
chthyosaurus, and Mixosaurus, the last the least specialized. 
