38 
THE aEOLOGIST. 
limestones of the Beauce and the Brie. Calcareous debris is rare : and 
grains of iron and feldspar still more so. On the plateaux the residue of 
Isevigation is very variable, even in the vegetable soil covering the same 
rocks. Thus on the plateaux above Gurches and Mendon, it rises to 70 
per cent. ; but more to the south, towards Saclay, it is reduced to a few 
hundredths. In the valleys, also, it varies, not only in the different valleys 
but also in the longitudinal and in transverse directions. The proportion of 
fine sand is also very notable in the bottom of the valleys ; on the banks of 
the Seine and the Marne it varies from a few hundredths. Clay is found also 
ia all the soils round Paris, sometimes pure, sometimes in the state of marl 
associated with lime. The soils which cover the plateaux formed by the 
lacustrine rock of the Beauce and the Brie, are particularly rich in clay. 
At Crenilly and yillejuif the proportion of clay is above 50, and it may 
sometimes reach to 90 per cent. But the clay is especially concentrated 
in the bottoms of the valleys, whether they be dry or wet. 
The examination of the constituent mineral substances shows that the 
soil comes in part from the subjacent rocks, and partly from the rocks in 
the neighbourhood ; and that it must not be always regarded as a disaggre- 
gation 1)1 situ, for we often find that in limestone rock the vegetable soil 
contains not a trace of calcareous matter ; and, vice versa, a highly cal- 
careous soil over a clay base. The vegetable soil M. Delesse considers as 
decidedly belonging to the " terrain de transport," or drift, as shown by 
the sand, gravel, and innumerable rolled fragments it contains. 
The practical value of M. Delesse's map is that, in indicating the minera- 
logical composition of the soil in the Paris district, it is easy to see what 
lands should be marled, and which should be drained, and to what extent, 
and with what materials, manures and extraneous substances should be 
economically employed in agricultural operations. 
TJeher Hiterfdhrter und Crustaceenreste in der unieren Dyas, oder dem 
unteren Rothlierjeiiden, der Gegend von Sohen Elbe. Von Dr. H. B. 
Geinitz. 
0)1 Animal Tracks and Crustacean Eemains in the Loiaer Dyas, or in the 
Lower Permian Sandstones of the Strata of the Higher Elbe. By Dr. 
H. B. Geinitz. (Extracted from the ' Isis ' of Dresden.) 1862. 
Dr. Geinitz, undismayed by the severe criticism he received at the 
hands of Sir Roderick Murchison, ('Geologist,' January, 18()1,) proceeds 
systematically to describe the fossils which are found in his so-called Dyas 
strata of Central Germany. Mrs. Josephine Kablik, a lady who cultivates 
natural science in that neighbourhood, has discovered several interesting 
fossils, which are described and figured in the work before us. 
The Dalmanites (?) Kablil'ce, Geinitz, is figured. It is a small Trilobite, 
which Geinitz considers ma}^ belong to the Silurian genus Dalmanites. Dr. 
Geinitz also figures a reniarkable Phyllopod crustacean, somewhat re- 
sembling the Branchipus stagnalis of Linnjeus, which he considers to be a 
new genus, Kablikia. The KabliJcla Dyadica, Geinitz, is found in the coal- 
slates of the Lower Dyas, near iS^ieder-Stepanitz, on the Higher Elbe. The 
original specimen is in the Dresden Museum. 
The limestone slates of the Lower Dyas have afforded evidence of im- 
pressions, considered by Dr. Geinitz to be those of a Crustacean, the speci- 
mens of which are also in the Dresden Museum. They are somewhat 
similar to those which Hall has figured in the ' Palaeontology of ]S"ew York/ 
considering it doubtful whether they belonged to Crustacea or Fishes. 
The paper is illustrated with two well-executed lithographic plates. 
A 
