SCIENTIFIC PAPERS 



OF 



ASA GRAY 



SELECTED BY 



CHARLES SPRAGUE SARGENT 



VOL. II. 



ESSAYS; BIOGRAPHICAL SKETCHES 



1841-1886 



BOSTON AND NEW YORK 



HOUGHTON, MIFFLIN AND COMPANY 



(Sfre fttoersi&e Press, £amliri&0? 



18S9 



