phenomena, which found expression naturally enough 
in a similarity of result when they came, independently 
of each other, to treat their respective branches of 
knowledge. That fundamental agreement in outlook, 
again, took its rise, it is safe to presume, in the days 
when they enjoyed constant access to each other, and 
freely and thoroughly discussed all the topics and prob- 
lems that presented themselves to one or other of them ; 
it was the legitimate fruit, in short, of their loyal and 
assiduous cooperation in the laborious pursuit of learn- 
ing when undergraduates together in Upsala. Already 
at that period, we may confidently suppose, they had 
each evolved and framed a system of treatment for the 
science he was more especially interested in, those two 
systems being, however, by reason of their originators' 
community of thought and experience, to all intents and 
purposes, one and the same. At this length of time it is 
quite out of the question for us to apportion to each of 
the two brother investigators his due and rightful share in 
the joint result; we can but at the best venture a rough 
conjecture on the basis of those differences in their 
temperaments which have been depicted in the fore- 
going pages. In some particulars, it is true, a diver- 
gence of view makes its appearance, the most conspicu- 
ous perhaps being, that, in reference to the arrange- 
ment of Classes and Orders, ARTEDI insists over and 
over again on the necessity of them being natural in 
origin, whereas LINNAEUS allows other considerations to 
have some deciding weight in the matter; as far as that 
goes, the former is ahead of, or more modern than the 
latter. Even in his Preface ARTEDI says, "... before 
everything I have urged that the Orders should by all 
means be natural" - "but such Orders ought 
not to be admitted as separate closely allied fishes one 
from another and combine together those that are not 
related - -". LINN^SUS, on the other hand, writes 
that, cseteris paribus, naturaUOrders are superior to ar- 
tificial ones, but adds resignedly that the Classes depend 
upon the agreement of the Genera in certain respects, 
