Geology, 4"C« of Malhay^ L. C. 



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green base, effervescing violently on exposure to acids, and 

 more or less powdery and soft. The nodules which it con- 

 tains are of milky translucent quartz ; and vary from the 

 size of the smallest grain, to that of a child's head ; the 

 latter being rare. 



They are sometimes so abundant as to be in contact i 

 at others they are in less number. When large, they are 

 frequently arranged in lines. The small granular species 

 resembles in its appearance a loose sand stone ; but when 

 of compact texture and free from nodules, it becomes a 

 brown limestone. It often contains imbedded balls of a 

 brown calcareous matter, hard, and of fine grain. It is 

 evidently an independent concretion. 



This rock and more especially the coarse grained spe- 

 cies, is rich in organic remains of the kind assigned by 

 writers to the transition formations. 



A very slight examination discovered four varieties of 

 orthoceratite, in imbedded fragments, differing in the num- 

 ber and construction of their transverse septa, and in the 

 proportion of their length to their breadth. Three of them 

 taper towards one end. The sides of the fourth are paral- 

 lel. One fragment is three inches broad, seven inches 

 long, and has eight septa. Another is six inches long by 

 one inch in breadth, with five transverse septa and one 

 longitudinal septum dividing it into two equal parts. A 

 third is five inches long, by one and a half broad ; and has 

 eight septa, each having a ring or circlet in its centre 

 thus : — 



Favosite and chain madrepore are not uncommon. En- 

 crinites, pectinites, terebratulas and strombites are particu- 

 larly plentiful. 



The dull brownish blue Limestone, so often instratified 

 with the primary rocks of these mountains is also inclosed 

 in this conglomerate, in single layers, a foot or so thick, or 



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