178 Scientific Intelligence—Geology. 
marsupials did not exhibit the peculiar disproportion of the extremities 
characteristic of the kangaroos, but were possessed of legs of nearly equal 
length like the wombat. The species of marsupial quadrupeds already 
known to inhabit Australia, form, as Cuvier observed, a small chain 
of animals, representing the quadrupeds of America and Europe, which 
was now rendered more complete by the discovery of extinet genera re- 
presenting the pachydermata, and equal to the medium bulk those ani- 
mals now attain.— Association Report in Atheneum, No. 886, p. 956. 
3. On the influence of Fucotdal Plants upon the formations of the 
Earth ; on Metamorphism in general, and particularly the Metamor- 
phosis of the Scandinavian Alum Slate. By Prof. G. Forchhammer. 
—lIt was remarked by the Professor, at a meeting of the British Associa- 
tion, that geologists had occupied themselves by extensive observations on 
the beds of sand and clay which have been carried into the ocean, but few 
have paid any attention to the soluble salts which are removed from the 
dry lands by the action of rain. Thus large quantities of potash and 
lime are constantly being carried into the ocean. The conditions of 
marine vegetation were next examined, and the analysis given of a great 
many fucoidal plants, all of which contained an exceedingly large amount 
of potash, often as much as five, and in some cases eight, per cent. Sea- 
water is found to contain but little of this alkali; it must, therefore, be 
concluded that the plants of the ocean have the power of separating the 
potash readily. Of magnesia, about one per cent. of the weight of the 
dried plant was generally found in the ashes. This chemical constitu- 
tion of the ashes of the fucus tribe, explains several great phenomena in 
the general nature of life; and it was suggested that, by returning the 
sea-weed to the land, in the state of manure, we should be restoring to 
it the potash of which it had been deprived. The memoir then entered 
extensively into the question of metamorphism, and gave an examination 
of the clay of the Scandinavian district. It was then shewn that the 
formation of beds, where fucoidal plants have grown, had a considerable 
influence on their structure and composition, as they would derive many 
of their constituents from them. It was conjectured that the conditions 
of the alum slate of Scandinavia were thus modified, As this paper will 
be printed entire in the Reports of the Association, we give but a short 
abstract. 
Prof. Liebig made some remarks on the necessity of alkaline bases 
for plants, and on the remarkable facts brought forward by Prof. Forch- 
hammer, that whilst sea-water contained, in 1000 grains, only 1 grain 
of potash, so large a portion should be found in the fucoidal plants. Mr 
Lyell observed, that the attention of chemists being turned to these great 
geological questions, he anticipated important results to science. He 
had visited the district, and confirmed the statement given.— Atheneum, 
No. 886, p. 955. 
4. On the Fossil Fishes of the London Clay. By M. Agassiz,—The 
group of fish peculiar to the London clay, whose remains are particu- 
larly abundant in the Isle of Sheppy, do not exhibit those strange forms 
which distinguish most of the fish of the more ancient formations ; but 
every thing reminds us of the fish living in the present seas. The ex- 
amination of these remains is attended, however, with difficulty, on 
account of the state in which the specimens are found, imbedded in hard 
