J.D. Hooker, Introductory Essay to the Flora of Tasmania. 313 
_ that he has failed to establish on independent evidence the doc- 
_ trines of variation and progressive specialization, or to co-ordi- 
nate his attempts to do so with the successive discoveries in 
_ physical science. 
_ _ 88, Before dismissing this subject, I may revert once more to 
_ the opposite doctrine, which regards species as immutable crea- 
_ tions, and this principally to observe that the arguments in its 
_ favor have neither gained nor lost by increased facilities for in- 
_ Yestigation, or by additional means for observation. The facts 
_ are unassailable that we have no direct knowledge of the origin 
of any wild s ecies; that many are separated by numerous 
_ * Means of investigation must be considered as cl il t 
_ Snigin of life itself = brought to light. oe 
89. Of these facts the most important, and indeed the only 
: Sey affords a tangible argument, is that of genetic resem- 
= Ry To the tyro in Natural History all similar plants may 
‘have had one issimi 
inn ® pursuits 
erally lost sight of; the systematist seldom 
) 1860, 
SECOND SER 
€ species itself ig 
Fg 
