436 
POPULAR SCIENCE REVIEW. 
South of Scotland Silurians. — Mr. J. D. Brown read a paper on these 
before the British Association at Edinburgh. The object of the paper was to 
show that the Silurian rocks of the south of Scotland, as developed in Dum- 
friesshire and Peeblesshire, are not all one geological epoch, as has been 
hitherto supposed, but belong to two different epochs — a lower one repre- 
sented by the Moffat rocks, well known by their beds of anthracite shales 
and graptolites, and an upper series of later age, which lie unconformable on 
the Moffat rocks. These beds have been long known at Wrae and Glen 
Cotho, and more recently in Galashiels, through the exertions of Messrs. 
Lap worth and Wilson. 
Neiv Fossil Reptiles from the Cretaceous and Tertiary Formations. — Pro- 
fessor C. 0. Marsh describes several of these remains in Silliman’s American 
Journal” for June. The remains were collected by the Yale College party 
'during their explorations last summer in the Kocky Mountain region. The 
specimens from the Cretaceous formation are of great interest, as they 
further illustrate the remarkable development in this country, both in 
ioumbers and distinct forms, of the Mosasauroid Keptiles, which appear to 
have been comparatively rare in other parts of the world. Fortunately, 
moreover, some of these remains serve to clear up several obscure points in 
the structure of these reptiles, and prove conclusively that they had a well 
developed pelvic arch and posterior limbs ; although up to the present time 
no satisfactory indication of this had been discovered, and the eminent palseon- 
tologists who have recently made these animals an especial study consider 
them probably destitute of these extremities. The remains found in the 
Tertiary deposits are also of importance, since they show that types of rep- 
tilian life, almost unknown hitherto from that formation in the West, were, 
in one of the ancient lake basins at least, abundantly represented there 
during that period. 
A huge Pterodactyl. — We learn from the American Naturalist” (July) 
that Professor Marsh states that the Yale College party obtained, in addi- 
tion to the cretaceous fossils already described, several specimens which in- 
dicate a huge flying reptile, which he names Pterodactylus Owenii. The 
bones discovered ^‘indicate an expanse of wings not less than twenty feet.” 
The remains were found by Professor Marsh in the upper Cretaceous forma- 
tion of Western Kansas. This is the first occurrence of the pterodactyl 
in America. 
The Sivatherium Giganteum. — Dr. J. Murie, F.Z.S., read a paper before 
the British Association at Edinburgh, stating the systematic position of the 
extinct Sivatherium Giganteum, in relation to the deer, antelope, and other 
animals of the same species. The author introduced 'The paper by some 
remarks concerning the labours of the late Dr. Falconer and Sir Proby 
Cautely. These eminent men, the former a distinguished graduate of the 
Edinburgh University, brought to light, in their researches of fossil fauna 
of the Sewalik Hills, several remarkable mammalian forms. The sivathe- 
rium, one of these, as attested by its remains, must have attained the size of a 
full-grown elephant. It appears, however, to have been a ruminant. In some 
respects deer-like, in others more resembling the antelopes, still stranger it 
seems to have had some of the characteristic features of pachyderms, the 
tapir for example. Dr. Murie went on to show that it belonged to those 
