ORDER I. PRISMATIC LIME-HALOIDE. 81 



in parallel laminae. Thus masses are formed con- 

 sisting of alternating layers of the two individuals. 

 Globular, reniform, coralloidal shapes : surface 

 drusy, composition columnar, the individuals being 

 often very delicate, but also occurring of various 

 dimensions, faces of composition irregularly streak- 

 ed. Massive : composition columnar, either pa- 

 rallel, or divergent, or irregular, and of different 

 sizes of individuals. 



OBSERVATIONS. 



1. Although several varieties of the present species had 

 long ago been separated from the rest of the Lime-haloides, 

 and more particularly from the rhombohedral one, and 

 erected into a particular species, under the name of Arra~ 

 gonite ; yet there are still some, which to this moment we 

 find united with it in several mineralogical systems. The 

 determination of a species is not attended with the slightest 

 difficulty, as long as it is possible to obtain correct infor- 

 mation of the form or regular structure of a mineral, of 

 its hardness and specific gravity. In fact, those varieties 

 which have not hitherto been united with the species of 

 prismatic Lime-haloide, are so much compound, that the 

 above mentioned properties can only be observed with 

 great difficulty, or not at all. The component individuals 

 of Flosferrl, particularly that of Eisenerz in Stiria, are 

 so minute, that their form and structure is withdrawn from 

 the eye. At Hiittenberg and in other localities of Carin- 

 thia, also at Torotzko in Transylvania, there are varieties 

 of the same mineral, similarly compound, in which, how- 

 ever, the size of the individuals is considerable enough to 

 allow the regular forms and cleavage to be ascertained, and 

 above all, to be sufficiently distinguished from those of rhom- 

 bohedral Lime-haloide. In the same way, as in the pre- 

 ceding example, it is necessary to proceed in every similar 



VOL. II. F 



