PLATE I. 



Fig. 1. Aerosiderite, Toluca, Mexico. Etched slab showing coarse Widmanstatten 

 figures and elongated nodules of troilite. One-half natural size. 



Fig. 2. Aerosiderite Hamilton Co., Texas. Etched slab showing delicate Widman- 

 statten figures and radiating inclusions of troilite. One-fourth natural size. 



