THE SAGAR DISTRICT. .57 



too, together with the similarity of paste, serves to connect them with 

 these amygdaloidal varieties, which, as elsewhere, in trap formations, 

 here most commonly occupy the lower positions. 



No. 13 is an amygdaloid which has been thought to resemble the 

 toadstone of England. It has a black homogeneous paste containing 

 chalcedonies, calcareous spar, and green earth. The former are often 

 geodes coated externally with calcareous spar, and internally lined with 

 minute crystals of quartz with calcareous spar filling up the cavity. 

 Where green earth occurs in the same cell with siliceous crystals, the lat- 

 ter appear in a decaying state. The size of these imbedded portions do 

 not, in general, exceed a nutmeg, although the chalcedonic geodes, &c. are 

 sometimes a little elongated to the extent of three or four inches, and their 

 sides are compressed. 



No. 14 has the same paste as the former, though softer, and except- 

 ing green earth, has the same imbedded minerals ; and when these are of 

 a moderate and usual size, very pretty specimens of the whole rock are 

 afforded, but in general this variety of amygdaloid envelopes very large 

 sized portions; — a cylindrical geode of amethystine quartz was found 

 measuring thirteen inches in length by two and a half inches in diameter. 

 It was coated internally with beautiftd quartz crystals, with calcareous spar, 

 as stated in the previous specimen, filling up the cavity, and this mineral 

 also coated the geode externally, and was seen much in splashes in the 

 paste proximate to the cell. As regards these amygdaloids, it would seem in 

 proportion as the contained mineral is large, so is the containing matter soft 

 and friable, though still retaining its colour, a black, when fresh fractured. 



No. 15. — Paste as before enveloping green earth, chalcedonies, and 

 zeolites, the latter predominating. 



Q No. 



