THE 



r AMERICAN 



JOURIAL OF SCIENCE AND AETS. 



[SECOND SERIES.] 



A.RT. XXIL — Thoughts on Sjjecies ; bj James D. DaxA, 



4 * 



(Read before the Aniericajj Association at Montreal, Aug. 13th, 1857.) 



While direct investigvation of individual objects in nature is 

 the true method of ascertaining tlie laws and limits of species, 

 'W'e have another sour(ie of suggestion and authority in the com- 

 prehensive priuQipIes that pervade the universe. The source of 

 doubt in this vSynthetic mode of reaching Vutli consists in our 

 imperfect appreciation of universal law. But science has already 

 searched deeply enough into the different departments of nature 

 to harmonize many of the thoughts that are coming in from her 

 wide limits; and it is well, aS we go on JXt' research, to compare 

 the results of observations with these utteriugs of her universality. 



I propose to present some thoughts on species from the latter 

 pomt of vieWj reasoning from central principles to the circum- 

 ferential, and, if I mistake not, we shall lind the light from this 

 direction sufficiently clear to illumine a subject which is yet in- 

 volved in doubts and difficulties. 



The questions before us at this time are 



1. What is a species? 



2. Are species permanent ? 



anations 



1- yVhat IS a sjyea'es. 

 . J} }^ common to define a species as a gr 

 individuals as are alike in fundamental qu 



SECOND SERIES, VOL. XXIV, NO. T2. — NOV., 1847. 



39 



such 



