Geology and Natural History. 255 
itself upon us whether it be not possible that all Lichens arise in 
. i i 
der Gonidien-frage, 1872, since which he has not returned to the 
inquiry in print. It has been continued, however, with great 
interest by others, and if lichenologists have generally looked 
askance at it, physiologists have done their best, we may say, to 
show it favor. 
Known already among lichenologists by studies of the most 
sincere and thorough kind—of which I will refer only to his 
Beitrige z. Kenntniss des Baues u. Lebens der Flechten 
dener. It had sometimes seemed as if the general, more or less 
harsh and subjective criticism which makes so large a part of 
even scientific controversy had been all on one side in this debate, 
could well expect any satisfactory proof. ? 
Most interesting was it therefore to every student of the Lichens 
that the keen observer to whom we have referred should buckle to 
the contest in the most weighty dispute that ever arose in this 
humble realm of vegetable nature. The long-promised second part 
of Dr. Minks’s Beitrige, with full illustrative plates, has not yet 
however made its appearance here and we have only an abstract 
