FIFTH REPORT OF THE DIRECTOR I908 2IO, 



The following measurements served to identify the occurring 

 forms: 



LETTER 



ANGLE 



NUMBER 

 OP 



MEASURED 



CALCULATED 





3." 



























1 12 



: 1 102 



3 



45 



12 



45 



3 



P"- 



; 





01 1 1 



: 0554 



5 



95 



22 



95 



34 



<?.: 



//. 





01 12 



: 0881 



4 



56 



14 



56 



32 



//.. 



a 





0881 



: 1 120 



4 



30 



5° 



30 



47 



p. 



m. 





1 1 1 



: 4041 



1 



3i 



14 



31 



io£ 



p. : 



K\ 





10 1 1 



12131 



4 



29 



4 



29 



2 



K; 



A f 





2131 



: 3121 



1 



35 



33 



35 



36 



p.: 



<> '. 





1 1 1 



: 8.5.13-3 



5 



35 



57 



35 



47 



'. : 





8-5 



13-3 



: 13-5-8.3 



1 



43 



22 



43 



x 3 



p.: 



s: 





1 1 1 



: 17. 13 .30 4 



5 



42 



43i 



42 



40 



5:: 



sf 



I7-I3 



3°-4 



: 30. 13. 17. 4 



1 



5o 



27 



50 



33 



t: 



i 



3-13 



16.8 



: 3-16.13.8 



4 



17 



3 1 



17 



47 



t: 





3-!3 



16.8 



: 13. 3. 16. 8 



4 



69 



6 



69 



1* 



2 Calcite from Jersey City, N. J. 



Among the minerals recently collected from the Erie railroad 

 open cut which is being excavated through the Jura trias diabase at 

 .Jersey City are several specimens. of calcite which present an inter- 

 esting instance of parallel grouping somewhat similar to that pre- 

 viously noted from Plainfield. These specimens, which were col- 

 lected by Mr James G. Manchester, have through the courtesy of 

 Mr Manchester been made available for study. The calcite occurs 

 in veins in the diabase associated with datolite, apophyllite, natro- 

 lite and stilbite all beautifully crystallized. The compound crystals, 

 like those from Plainfield consist of two superposed habits corre- 

 sponding to two generations of calcite deposition. The earlier 

 generation is represented by crystals of a simple rhombohedral 

 habit consisting of the negative rhombohedron (0775). In a 

 number of instances these rhombohedral elements occur uncom- 



