JOURNAL oF GrEoLocy, VoL. XXIX, No. 3 PLATE VI 
A. Microcline microperthite (eutectoperthite), called 
“‘Orthoclase,”” East DeKalb, St. Lawrence County, New York. 
Polarized light. X30. Specimen gg5x. 
B. Antiperthite (hyperperthite), called ‘‘Orthoclase,” var. 
Delawarite,”’ Delaware County, Pennsylvania. Polarized light. 
X30. Specimen got. 
