SYENITE AND PORPHYRY OF NEW JERSEY 



579 



minute tufts. Orthoclase also shows its twinned development 

 here. The larger aegirites are associated with small but numerous 

 crystals of titanite and a little biotite. A few patches of ilmenite 

 are noticeable, and under high power a little perovskite and apatite 

 may be seen. Cancrinite and hauynite are quite minor constituents, 

 and there is very little development of carbonates. The general 

 mineralogical development is quite similar, except as regards 

 texture, to that of the nephelite syenite itself. Though orthoclase 

 exists in minor amount in some cases, ordinarily it is an important 

 constituent. 



TABLE II 



I. Nephelite porphyry, Beemerville, N.J. H. S. Washington, anal. Incomplete. 

 II. Nephelite porphyry, Beemerville, N.J. M. Aurousseau, anal. Incomplete. 



III. Average( excluding AI2O3 of I) of I and II. 



IV. Tinguaite, Monte Mulatto, Predazzo, Tyrol. M. Dittrich, anal. J. Romberg, 

 Sitzb. Preuss. Akad. Wiss., I (1902), p. 748. 



V. Nephelite porphyry, Wudjavrtschorr, Upmtek, Kola. V. Hackmarm, anal. 



V. Hackmann, Fennia, XI (1894), p. 151. 

 VI. Tinguaite, Hooper's Inlet, Dunedin, New Zealand. P. Marshall, anal. P. 



Marshall, Quar. Jour. Geol. Soc, XLII (1906), p. 396. 

 VII. Leucitite, Etinde Volcano, Kamerun. M. Dittrich, anal. Sitzb. Preuss. 



Akad. Wiss. (1901), p. 299. 

 VIII. Norm of III. Symbols, II. (6) 7. i. 3. Janeirose. 



