TABLE OF SECONDARY FORMS. 219 



Secondary forms. How they may be derived. 



Fig. 291, 



b. The planes being sca- 

 lene triangles. 



Fig. 292. 



c. The planes being 

 rhombs. 



The rhombic dodecahe- 

 dron 



From the rhomboid, particu- 

 lar planes of Modification 

 d, h, i, I, or n. 



hexagonal prism. 



Modification a, or c. 



, rhomboid, Modifi- 

 cation d, h y i, /, w, orjp. 



cube, Modification 



, regular tetrahedron, 



particular Modification be- 

 longing to class b. 

 ,...,.. regular octahedron, 

 Modification e. 



