SALMON- 
: — ON THE FORMATION OF ORE-VEINS. 
355 
sion of the creature through the water, the medium in which it is 
destined to pass its existence. 
From the fish we pass upwards to the Reptiles, in which we have 
a considerable advance of organization, and the first decided traces 
of fore and hind limbs or legs for terrestrial or amphibious locomo- 
tion. The heart of reptiles has but one ventricle, and the circulation 
of their blood is sluggish and slow ; and indeed their whole organ- 
ization is far inferior to the animals of the next and highest class of 
animals, the Mammalia. 
In these last the blood is warm ; the heart is possessed of auricles 
and ventricles ; the circulation free and rapid ; and the internal 
skeleton of the highest perfection of development. At the top of the 
class stands man, the most intellectual and most highly organized of 
all created things. 
GENERAL CONSIDERATIONS ON THE FORMATION OF 
ORE- VEINS. 
(Translated from the German of Professoe Bernhard Cotta, of 
Freiberg, with an Introductory Notice on the Studij of Mineral 
Veins and Metalliferous Deposits, hij H. 0. Salmon, Esq., Plymouth.) 
I PROPOSE, from time to time, in the pages of this magazine, to 
bring before geologists and geological students translations or 
abstracts of some of the most authoritative memoirs of foreis'n 
geologists on the subject of mineral veins and metalliferous deposits. 
Notwithstanding the great commercial value of the metallic mines 
of the United Kingdom, the subject of mineral veins and metal- 
liferous deposits has not, of late years, occupied the serious attention 
of many men of recognized scientific position in this country : the late 
Sir Henry de la Beche, Mr. W. Jory Henwood, and Mr. Warington 
Smyth are those best known. The strong distaste which un- 
doubtedly exists to inquiries in this field of geology is due to many 
causes which it would be out of place to discuss here. I may 
nevertheless be permitted to say that, however just this feeling may 
