1888. | NEW YORK ACADEMY OF SCIENCES, 219 
dolomite bed, St. Ann’s avenue, 145th street. The faces of the 
trapezohedron are striated, parallel to the octahedral faces. The 
same locality yielded massive pyrite. 
Brilliant, finely modified crystals in dolomite, Harlem Canal 
WeANt. )). 
nae penetrating tourmaline, Jumel Grounds, Washington 
Heights. Also at 172d street and Tenth avenue. 
Massive in dolomite, Harlem and Kingsbridge. 
Marcasite. In reniform and globular masses, with traces of 
crystallization. Excavations for addition to Met. Museum of 
Art, 1886. With calcite and quartz, Aqueduct shaft No. 22. 
Pyrrhotite. Fort George. 
Menaceanite. In thin brilliant plates, occasionally showing 
crystal edgesand angles. 56th street, Sixth and Seventh avenues; 
Fifth avenue, 104th street; Lexington avenue and 101st street ; 
Morrisania. 
Washingtonite. The plates sometimes an inch across, 56th 
street, Sixth and Seventh avenues. (D.S. Martin.) 
Crichtonite (?) In smoky quartz. Found by W. H. Pease 
in the drift (I. C.). This was very probably menaccanite. 
Magnetite. In seams of quartz in gneiss, 100th street, Lex- 
ington avenue; Jumel Grounds, Washington Heights; 56th 
street, Sixth and Seventh avenues. 
Crystallized in lamellar and radiated forms, between leaves of 
muscovite, Riverside Park and elsewhere. 
Chromite. Octahedral crystals in serpentine, 60th street, 
North River. 
Limonite. Bog iron ore, in large beds abuut the island 
Rob.). In low grounds east of Eighth avenue, and north of 
ixth street to 32d street. 
In masses often iridescent, east bank of Harlem River. 
In globular forms resembling shot, 55th street, Sixth and 
Seventh avenues, and elsewhere. 
Columbite.’ First discovery of this mineral on the island in 
the summer of 1887, at the granite vein, Fort George. 
Vivianite. Associated with stilbite and epidote in fissures in 
gneiss. Harlem (J. W. Webster). 
Siderite. In perfect rhombohedral forms (S. C. H. B.), 57th 
1 In collection of Mr, George F. Kunz. Described by him in Transa 
tions of the Academy. 
