of Crystalline Combinations. 417 
SQUARE-PYRAMIDAL SYSTEM. 
Relations of Edges, §c. 
The forms are in a parallel position. 
The faces of the four-sided pyramid truncate the scalene edges of the eight-sided 
pyramid. (S, 7.) 
The E. C. are parallel to themselves and to the truncated edges. 
++eeeeeeeee-- and to the line bisecting the lateral edges of the four-sided py- 
ramid. : 
The forms are in a diagonal position. 
The faces of the four-sided pyramid truncate the principal edges of the eight-sided 
pyramid. (S. T.) 
The E. C. are parallel to themselves and to the truncated edges. 
veoe.++eeeeeee and to_the line bisecting the lateral edges of the four-sided pyramid, 
The forms are in a diagonal position. 
The faces of the eight-sided pyramid, adjacent to its scalene edges, appear in pairs in 
the place of the terminal edges of the four-sided pyramid. (8S, T.) 
The E. C. are parallel to themselves and to the replaced edges, 
«ss eeeseeeeeee and to the scalene edges of the eight-sided pyramid, 
The forms are in a parallel position. 
The faces of the eight-sided pyramid, adjacent to its principal edges, appear in pairs in 
the place of the terminal edges of the four-sided pyramid. (S. T.) 
The E. C. are parallel to themselves and to the replaced edges. 
seeveeeesseeeee and to the principal edges of the eight-sided pyramid. 
The forms are co-ordinate pyramids in a parallel position. 
E. C. parallel to the terminal edges of pQ. 
The forms are in a parallel position. 
E. C. horizontal. 
3H 2 
