B. W. Frazier— Axinite from, Bethlehem, Penn. 445 



Table III would lead one to infer that there must be some 



similarity in habit between axinite and datolite. Further com- 



contirm this conclusion. In an examination of the 



published descriptions of crystals of axinite from various local- 



common to the crystals of datolite from all of the four local- 

 ities given by Dana in his article, cited above Of the forty- 

 two simple forms yet discovered in axinite. twenty-eight corre- 

 spond to forms oceurring in datolite. Conversely all of the 

 eleven simple forms of datolite mentioned as common to all 

 tlie localities given (equivalent to sixteen simple forms of 

 axinite) are represented, partly or wholly, by corresponding !'. >rms 

 of axinite, and ten of these forms of datolite are represented by 

 frequently occurring planes of axinite. As datolite crystals are 

 far richer in planes than those of axinite, there must be many 

 forms in the former mineral winch are not represented by cor- 

 responding forms of the latter. From what has been adduced, 



•'ing tonus of the two minerals, there is a close correspondence 

 between them in habit as well as in angles. 



Calamine is another mineral showing analogies in its crystals 

 to those of datolite. The similarity between the crystalline 

 forms of these two minerals seems to have been observed by 

 Miller. This I infer from his having chosen positions for both 

 minerals which would bring out the resemblance between them, 

 and from his having placed datolite in his edition of Phillips' 

 Mineralogy immediately after smithsonite, by which name he 

 calls Brongniart's calamine. I am not aware of any express 

 statement of such a resemblance by him or any other mineralo- 

 gist. The similarity will be made sufficiently plain by a com- 

 parison of the following angles between corresponding planes 

 of the two minerals, taken from the work just quoted — 



OK) : Oil 58° 20' 57° 43' (HO : 021 



00) : 101 25° 40V 26° 34' 001 : 101 



100:110 51° 56$' 51° 38' 100:120 



001 : 211 48° 54' 4<>° 47' 001 : 221 



100: 411 31° 19' 30° 36' 100: 121 



Miller's fundamental pyramid, I (111), for datolite is Dma's 

 clino-pvramid 22 (121). The fourth column gives the parame- 

 ter's of the planes in question, if referred to Dana's fundamental 

 form for datolite. 



