PHYSICS AND NATURAL HISTORY OF GENEVA. Ohi 
dislocation and plissement, distinguishable from the banks of the Isar, in Bava- 
ria, as far as Lausanne, and continued, according to M. Favre, by the uplands 
of Boisy, in Chablais, and by Mount Salive. The direction of these points is 
in a right line, as M. Favre has shown on a geological chart of Switzerland. 
Thus the molasse has been cleft throughout this whole line, and the subjacent 
jurassic limestone been lifted up—at no point, however, so high as on the site 
of Saleve. 
One of the last excursions of M. Favre was around Mont Blane, in which 
he especially examined the Bas-Valais, and found at Mont Chemin, near Mar- 
tigny, belemnites pertaining to the lias, which are found above the cargneule 
representing the lias. He found on the mountain of Maya, near the col lerret, 
echini and fragments of the branches of encrinites which characterize the up- 
per jurassic formation. The deposits in question are at about fifty feet from 
granitic rocks of Mont Blane, and are covered by considerable masses of erys- 
talline limestone. 
Professor F. J. Pictet read a memoir on the unrolled ammonites of cretaceous 
formations. ‘Till now these fossils have been found only in fragments, and it 
was easy to attribute to two distinct kinds, portions of the same animal. The 
author has pointed out many similar errors, which he has been enabled to cor- 
rect by means of more complete specimens. This memvir will form part of 
M. Pictet’s work on Swiss paleontology. In a note on the parallelism of the 
middie and upper cretaceous faunas, M. Pictet has aimed to show that the dis- 
tinction made by Orbigny, of eight cretaceous stages, although holding good as 
to large tracts, is insufficient for the study of details and of the succession of 
faunas. He compares the middle and lower stages of the Swiss Jura, the north- 
west of Germany and the south of France, and confirms the observation of M. 
Lory that the neocomian faunas differed according to their geographical posi- 
tion. Not that they have varied uniformly over their whole extent. By the 
side of numerous analogies we see local differences which evince either migra- 
tions or different, although simultaneous, physical influences. In the discus- 
sion which ensued upon the reading of M. Pictet’s memoir, some difficult ques- 
tions of science were broached. Among other things, the proximity, sometimes 
considerable, of analogous formations furnished with different fossils, was spoken 
of, and facts of the same nature were pointed out by M. Ciaparede in the dis- 
tribution of existing faunas, according to the depth of closely neighboring arms 
of the sea. 
The curious discoveries of M. Lartet, tending to prove the antiquity of the 
presence of man in western Europe, were the subject of communications from 
M. Pictet, which he has published in the Bibliotheque Universelle for 1861. 
<rofessor Thury stated his objections to the opinions of M. Marlot on the 
time occupied in the formation of the cone of Tinere, at the east extremity of 
Lake Leman. He has attentively explored the valley whence proceeds the det- 
ritus borne towards the lake, and he does not think that it can have furnished 
materials with the regularity supposed. On the contrary, it appeared to him 
that the quantity of material removed from the surface must have trequently 
varied. 
ZOOLOGY. 
M. Pictet exhibited moulds from two skulls of gorillas, whose diversity is 
sufficiently great to induce a suspicion of the existence of two distinct species. 
Dr. Dor presented important memoirs on vision, as well in man as in certain 
classes of animals. The author attributes myopy (short-sightedness) to a too 
great length of the axis of the ¢ye, while the opposite imperfection (hyperme- 
tropy) results from too short an axis. He has found between a myopic and a 
hypermetropic eye a difference of as much as fourteen millimetres in the length 
of the optic axis. M. Dor carefully distinguishes the effect of age on the 
