CONTENTS. 
Moonlight and Electric Light—C. B. Warring, Ph.D., : 
Discovery of a Locality of Trenton Limestone Rich in Ostracoid 
Entromostraca, etc.—Prof. W. B. Dwight, 
Some Notes on Amateur Photography—C. L. Bristol, 
Limit of Visibility for Minute Masses—Leroy C. Cooley, Ph. D, 
Real or Supposed Changes of Latitude—C. B. Warring, Ph.D. 
The Grand Centre of the Universe—C. B. oe. Ph. Dy 
Report of Chairman—April 24, 1888, ; 
Election of Officers—April 24,1888,  . 5 
The Cambrian System of Strata—Prof. W. B. Deena 
Discovery of Fossiliferous Strata of the Middle Cambrian at 
Stissing, N. Y.—Prof. W. B. Dwight, 
Report of Curator—Jan. 29, 1889, 
Some Simple Equations—C. B. Warring, Ph. Dy, 
Imaginary Quantities : Their Philosophy—C. Be Warring, Ph. D., 
Glacial Phenomena—Prof. W. B. Dwight, : : 
The Progress of Photography—E. Elsworth, 
A Curious Gyroscopic Phenomenon—C. B. Warring, Ph. D., 
Report of Chairman—April 23, 1889, : F : 
Election of Officers—April 23, 1889, 
Food Adulterations—E. Elsworth, 
Ferns—Gilbert van Ingen, 
The Theory of the Bicycle—C. B. eaniins Ph. Dy 
The Land Snails of Poughkeepsie—G. van Ingen, 
Preliminary List of Land Snails of Poughkeepsie— G. van 
Ingen, 
Sir William hereon and This Guncetatie Baercee ard ‘ie Re- 
lation of Nutation to Precession—C. B. Warring, Ph. D., 
Report of Curator—April 22, 1890, : : 0 
Report of Librarian—A pril 22, 1890, 
Report of Chairman—April 22, 1890, 
List of Specimens in the Eee arian Belonging Ag the conv of 
Dutchess, N. Y., 
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