354 G. H. Kinahan — Nomenclature of Schistose Hocks. 



in recent times, ice-preserved, in the wilds of Siberia, presents to 

 our consideration several points of indisputable cogency. 



1st. That the destruction was sudden, apparently simultaneous, 

 and succeeded immediately by conditions of climate under which the 

 process of decay was arrested. 



2nd. That these conditions of climate were continuous for a 

 lengthened period, as proved by the great accumulation of ice in 

 which the remains had been imbedded. 



3rd. That the region inhabited by these animals presented during 

 their existence a climate subject to the variations now proper to the 

 temperate zones, — a condition incompatible with the present declina- 

 tion of the terrestrial axis. 



4th. That the period of their destruction was presumptively at 

 mid- winter of the northern hemisphere; certainly between the 

 months of September and April of our present calendar.^ 



On the other hand, the constant supply of fossil ivory^ found within 

 the arctic limits, liberated from time to time we must presume from 

 the icy store-houses around, proves that the race producing it must 

 have been numerous, and occupied widely the zone which now pre- 

 sents an aspect so different from that under which these animals 

 must have existed. As a corollary to this ancient condition of what 

 is now the frigid zone, a corresponding disparity of climate must be 

 admitted for the temperate regions of to-day, consistent with the 

 former existence there of the extinct Hippopotamus, and of other 

 animals, the types of modern species confined to intertropical climates 

 under the present unvarying conditions of our planet. 



VI. — On the Nomenclature of Schistose Books. 



By G. H. Kinahan, M.R.I.A., etc., 



of the Geological Survey of the United Kingdom. 



n^HE term Quartzyte has been used to designate quartz-schist and 

 I seems to be generally adopted, while Argillyte is used by some 

 authorities in place of argillous or argillaceous-schist. I would there- 

 fore suggest that the other subgroups and varieties of schistose rocks 



1 The analogy between the conditions of the existing Bison of North America and 

 that of the extinct animals is striking ; the inference follows in regard to the climatic 

 and seasonal circumstances. Subjected to extremes of heat and cold in its natural 

 habitat, the Bison is endowed by Nature with a provision conformable to both. 

 During winter a thick coating of fine wool underlies its shaggy covering of hair ; 

 precisely as in the cases cited in the text. As summer approaches, this wintry garment 

 gradually falls off, and is succeeded by a thin coating of new hair, corresponding for 

 the time with that of the Buffalo of Asia and Africa', to which, as to the modern 

 Elephant and Rhinoceros, a warmer covering is at no time necessary. 



■^ Upwards of 600 mammoth tusks were last week offered for sale at the Ivory 

 Warehouse, London Docks. Some of these were from nine to ten feet in length, and 

 presented the peculiar double curve so characteristic of the tusks of H. primigenius 

 wherever met with. See Geol. Mag., 1868, Vol. V. p. 540, Plates XXII. and XXIII. 

 — Edit. Geol. Mag. . 



