a 



TAB. CCCIV. 



At first sight this looks like a very different modification 

 from the last. It is, however, only more perfectly accu- 

 mulated on the periphery of a wheel, as it were, united 

 in large faces, either upon opposite ends of crystals, like 

 the right hand lower figure, or mackle, and is sometimes 

 formed of a variety composed of many, partly belonging 

 to the left hand bottom figure. The ends become small 

 and rough around the series of tab. 3Q3, but large and 

 smooth around this; whilst, on the contrary, the radii of 

 the latter or column are generally most confused. 



