2S4 W.E.Ford — Herderite Crystals from Auburn, Maine. 



from Greenwood. Figure 1 is an idealized representation of 

 the tonus on a simple crystal, but shows them as nearly as 

 possible in their characteristic development. The crystals were 

 all elongated parallel to the clino-axis and, with one exception, 

 showed only the faces at one end of this axis. The crystals 

 were frequently broken and distorted in their development, as 

 is shown by figures 2 and 3. Figure 3 is of a very small crys- 



Fig. 1. 



Fig. 2. 



Fig. 3. 



tal, but one which ,was better adapted for measurement than 

 the larger individuals and which was also unique in that it 

 showed portions of the negative pyramid r (121) at the nega- 

 tive end of the clino-axis. 



The most prominent faces on the crystals were the clino- 



Fig. 4. 



Fig. 5. 



domes #(032) and v (031),_the pyramids ^(332) and n (331), and 

 the negative pyramids g (343) and r (121). The base c (001) and 

 the ortho-dome e(302) were always present, but only as small 



