. Natural-Historical Collections. 147 
Bisons in Lithuania.—The Bison, called in Polish Zuby, has disappeared 
from Europe, with the exception of the forest of Bialowiez, in Lithuania, wherein, 
as appears from an official return which has just .been published, there were, in 
1824, 543 large and small. The Russian government Hee taken measures for 
the enlarge of this valuable race of animals. 
Surasvuve of the Ammoniie.—M. Léopold de Buch draws the attention of 
naturalists to a new method of distinguishing and arranging the ammonites. 
Justly appreciating the fact that the structure of an animal is more constant and 
more connected with its general habits, i.e. with its natural history, than the 
external form or colour of its habitation, he seeks in the configurations which lie 
immediately under the thin exterior layer, or shell of these fossil animals, for 
characters by which the species may be advantageously determined. And the 
law which he has laid down is the. more valuable, as it affords an easy and pre- 
cise distinction between the ammonites and Nautili, which closely approximate, 
The great difference between these two genera of Cephalopodous Mollusca, 
consists in the siphon of the former being always dorsal, whilst that of the latter 
is never so situated ; and from this primary distinction all the minor differences 
result, as M. de Buch thus ingeniously explains them. 
The Nautilus protrudes a large siphon through the middle of its partitions, 
by which alone the animal is securely attached to the surface, on which the si- 
phon rests ; and the partitions are in general smooth and concave, without any 
flexures on the borders. But the delicate dorsal siphon of, the ammonite, is not 
sufficient to prevent concussion of the animal within its partitions. Other means 
of attachment are accordingly necessary, and the following provision is found. 
Below each partition there lie six lobes, symmetrically arranged around the cir- 
cumference of the shell. The first or ventral lobe, which is usually the most 
considerable, rests upon the back of the convolution which precedes it. - On the 
opposite side, the dorsal lobe advances itself towards the bottom to embrace the 
siphon ; and it is thereby divided into two cones, which are more or less sepa- 
rated from one another. At one-third of the height of the aperture from the 
back, the swperior lateral lobes are placed on each side, and lower down, the 
inferior lateral lobes are similarly arranged ; the latter being a little more elevat- 
ed than the ventral lobe. The separation of these lobes form the Se//a, or seats, 
so termed because the animal rests upon them ; and their distinctive names, are 
derived from those of the lobes. 
If the spire increases rapidly i in size, so that the last whorl envelopes all the 
others, the animal would require points of support for the additional part. The 
cardinal lobes are then almost lost in a number of little auxiliary lobes, which in- 
crease in number as the ammonite enlarges, and of which there are sometimes 
found as many as three, four, or five. These auxiliary lobes are very apparent in 
the family which has been named Serpentine after Reinieke, and, whenever they 
occur, are subject to determinate laws in the flexures of their margins. 
M. de Buch conceives that the animal finds additional attachment to its shell, 
by inserting its sac within the selle formed by the lobes ; and from the varieties 
which occur in the conformation, he proposes that specific characters shall be de- 
duced.— Ann. des Sciences Nat. July 1829. 
‘Thorite, anew Mineral Species, and Thorina, a New Earth.—The Rev. Mr. 
Esmark of Brevig in Norway has discovered a new mineral substance in small 
quantities in the syenite, which composes the island near Brevig. It is massive, 
black, brittle, and semi-hard. The vitreous lustre of its fracture resembles that of 
gadolinite. The surface is sometimes covered with a red coating. Its powder is 
dark brown ; its specific gravity 4.8. Before the blowpipe it gives out water and 
becomes yellow. M. Berzelins has appropriated to this mineral the name thorite. 
Some time since this celebrated chemist gave the name thorina to an earthy ox- 
ide, which he then supposed to be new, but which is only a phosphate of yttria. 
