OllDER VIII. GENERA AND SPECIES. 439 



H. = 50... 6-5. 

 G. =3-8 ... 5-3. 



Streak brown: G. = 4-8 and less, or 



4*8 and more. 



G. under 4-3 ; the colour being black : 

 streak without lustre. 



1. AXOTOMOUS. Rhombohedral. R = 85 59'. 



Combinations hemi-rhombohedral, with parallel faces. 



P + l = 91 20'. 

 2 



Cleavage, 11 oo, perfect. Traces of R. 



Streak black. 



Weak action upon the magnetic needle. 



H. = 5-0 ... 5'5. 



G. = 4-4 ... 4-8. 



Titanitic Iron. Vulg. ij. 397. 



2. OCTAHEDRAL. Tessular. 



Cleavage, octahedron. 



Streak black. 



Strong action upon the magnetic needle. 



H. = 5-5 ... 6-5. 



G. = 4-8 ... 5-2. 



Octahedral Iron-Ore. J. ii. 399. 



3. DC-DECAHEDRAL. Tessular. 



Cleavage, octahedron, very indistinct. 



Streak brown. 



Weak action upon the magnetic needle. 



H. = 6-0 ... 6-5. 



G. = 5-0 ... 5-1. 



FranWnite. ii. 403. 



4. RHOMBOHEDRAL. Rhombohedral. R =s 85 58'. 



Cleavage, R. Sometimes, R-.cc. 



Streak red ... reddish-brown. 



Sometimes a weak action upon the magnetic needle. 



