TRANSACTIONS OF THE SECTIONS. 91 
pebbles, but never striated, coming from the Alps, sometimes stratified, but without 
fossils, In Switzerland this formation covers a great part of the basin, and it is of 
great depth round Geneva and Berne. We think it is owing to the fusion of gla- 
ciers at the period of their oscillations. The glaciers of the Alps, those of Grindel- 
wald, of Bosson, and of the Aar, produce a similar diluvium at present, but upon a 
small scale. 
4, Ancient Alluvium with bones of Pachydermata—In the two countries this allu- 
vium is composed of rolled pebbles of moderate size, which do not come from the 
Alps situated in front, There are found in it bones of the Elephas Primigenius, 
(Mastodon angustidens), Rhinoceros Tichorinus, Bos Priscus, Cervus Euryceros, &c. 
This formation is altogether aqueous, and has nothing in common with those of the 
glacial epoch. In Switzerland this alluvinm rests on the miocene molasse, and in 
Piedmont on marine pliocene beds. 
If a parallel is attempted to be drawn between these formations and those of Scan- 
dinavia, Scotland, and North America, it should not be forgotten, that since the 
glacial epoch the coasts of these countries have been submerged beneath the sea and 
again raised above it, from which it follows that very recent marine deposits would 
take place, contemporary with or posterior to the scattered erratics. 
On certain extraordinary Peculiarities of Structure in the more Ancient 
Ganoids. By Hucu Mitier, Edinburgh. 
Mr. Miller began by stating, that it was his purpose to introduce to the notice of the 
Association in his paper a curious suite of fossils from the lower old red sandstone 
of Scotland, many of which were still without duplicate in the public museums of the 
empire, and but imperfectly represented in those of Russia. In one important respect 
' there attached to them a peculiar interest. They belonged to the earliest animals of 
the vertebral division, of which our knowledge is not rather inferential than direct. 
The most ancient fishes known to the geologist are the Placoids of the Silurian 
system; the next most ancient, the Placoids and Ganoids of the lower old red 
sandstone. Of the Placoids, however, little comparatively could be known; from 
their perishable cartilaginous structure, an entire species might be represented by 
but a few spines, teeth, or shagreen points ; whereas the Ganoids, from the peculiar 
armature of solid bone in which they were enveloped, continued to exist, not as mere 
ichthyic fragments, but as ichthyolites. Hence our absolute knowledge of the ancient 
forms and mechanism of ichthyic life was mainly to be derived from the study of the 
first Ganoids. In illustration of this remark, Mr. Miller submitted to the meeting two 
sets of specimens,—the one consisting of minute toothed ichthyodorulites,—those of 
the Homocanthus arcuatus, a Placoid of the lower old red sandstone, and a larger 
spine belonging to another old red Placoid, the Haplacanthus Marginalis; while in 
the other set, consisting of ganoidal remains, there occurred a specimen—specially 
referred to by Agassiz in his great work—which exhibited a considerable part of an 
oid red Ganoid,—the Osteolepis Microlepidotus. The Homocanthus and Haplacanthus, 
which, though previously known in the old red of Russia, had been only recently 
added to the fossil fauna of Scotland by the researches of Mr. Robert Dick of Thurso, 
were represented in the specimens by mere spines ; whereas the Osteolepis was in such 
a state of keeping, that Agassiz, from the very specimen before the Association, had 
_ determined that the creature was possessed of the sense of smell,—nay, he had even 
detected it in a certain peculiarity in the structure of the nostrils, restricted in the 
present time to those of a single fish,—the Lepidosteus of the American rivers. Under 
one occipital plate on the table there might be seen the remains of not only the upper 
part of the brain-pan, but also marked indications of auricular chambers, resembling 
those of the sharks and of some of the reptiles. Some of the other specimens exhibited 
the openings through which the eyes had once looked out. In a Dura Den specimen 
of Pterichthys,—the property of Mrs. Bonar of Cupar-Fife,—the very capsules of the 
eyes were preserved ; and we had thus evidence of at least the three senses with 
which these earliest of the Ganoids took note, in an incalculably remote period, of the 
sights, sounds and odours of the material world. 
There was a peculiarity in the mouths of some of the existing Placoids, to which 
Mr. Miller begged leave to call the attention of the Association. In some of the 
