1897.J NEW YORK ACADEMY OF SCIENCES. 329 



(1.5 mm.) in lengtb, and showed all the faces noted below, as 

 determined by the reflecting goniometer. 



a(lOO) ri(lll) 



c(OOl) r-(101; 



m(llO) Z(201) 



w(210) e(lOl) 



g(221) 1(102) 



(^(111) m(102) 



The simplest combination of forms observed was that shown 

 in Fig. 1 and composed of a(lOO), r(lOl), m(llO), c(OOl). 



Another crystal, Fig. 2, which was one of the three best de- 

 veloped showed rt(lOO), m(210), m(llO), rf(lll), /(20]), r(roi), 

 and c(OOl). The smallest cr^'stal of the lot had all the faces 

 noted. While this series of allanite crystals is on the whole 

 not as perfectly developed as those found by Professor Kemp at 

 Franklin Furnace and described by Dr. Eakle,* still many of the 

 crystals are larger, and no such large masses were found in the 

 Franklin Furnace material. 



Columbia University. 



NOTE ON A BERYL CRYSTAL FROM NEW YORK 



CITY. 



By Heinrich Ries. 



(Read March 15, 1897.) 



Beryl is not an uncommon mineral of the granite and pegma- 

 tite veins of Manhattan Island, but the crystals, although fre- 

 quently of large size, seldom show more than the prism faces. 



The crystal described below was found by Mr. Gilbert van 

 Ingen at Forth-ninth Street and First Avenue, and shows an un- 

 usually perfect development of terminal planes. It is a small 

 transparent individual, not more than -jL- inch long, with faces of 

 sufficient brightness to permit their determination with the Fuess 

 goniometer, and the angles read agreed quite closely with the 

 calculated ones. 



* Trans. N. Y. Acad. Sci., XIII., 102. 



