river, which, on re-elevation, formed the soil for fresh 

 growths, the alternation being occasionally broken by 

 the deposit of purely marine beds. The coal of this 

 age is mainly confined to countries north of the 

 equator, and was not probably under the influence of 

 extreme heat at the time of deposition. The coal of 

 the oolitic and cretaceous ages belong to the southern 

 hemisphere ; the tertiary coal is uniformly distributed 

 inespective of latitude. 



Before leaving this period let us carry our imagina- 

 tion back to its morasses and lagoons, scarcely raised 

 above the sea-level, and encircled by rising ground not 

 worthy to be designated hills, on which hung dank 

 mists, feeding the streams which flowed through the 

 masses of matted verdure. Let us picture to our- 

 selves, the erect naked Calamite, the columnar trunked 

 Sigillaria, the Lepidodendron, the graceful arborescent 

 ferns with their magnificent crowns of leaves,the climbing 

 Asteropliyllites, all combining to excite admiration, 

 but no lovely petalled flower broke the monotony of 

 this verdant scene ; the organs of reproduction were 

 not at that time enclosed in a covered receptacle, but 

 merely furnished with insignificant scales, and no 

 nature-painted petal, which now adorn so large a pro- 

 portion of plant life, ravished the eye as now with their 

 many coloured bridal garments. The first evidence 

 of a rnonocotyledonous plant occurs in the lowest 

 beds of the carboniferous series ; the spadix of an 

 Aroid, Pothocites, was found by Doctor Paterson in 

 the bituminous shades of the coal-measures, near 



