22 THE AMERICAN NATURALIST. [VoL. XXXIII. 
Dr. Baur’s interest in the more general problems of morphol- 
ogy, such as the origin of variations, was first keenly aroused 
at Clark University at a time when Weismann’s essays were 
the subjects of much general discussion. He always remained 
a steadfast Neo-Lamarckian, never forsaking the position he 
had taken in his inaugural dissertation, A perusal of Wagner’s 
and Eimer’s works convinced him that isolation and environment 
are potent factors in producing variation. A previous study of 
the giant land tortoises of the Galapagos, in connection with 
his turtle monograph, and further studies on a genus of lizards 
(Tropidurus) which has produced different so-called species on 
the various islands of the archipelago, led him to conclusions 
which his subsequent visit to the islands did not modify. It 
was, perhaps, fitting that one born in the year of the publi- 
cation of the Origin of Species should gain inspiration from 
the spot where the idea of the “ Origin ” was conceived. At 
the very outset, however, he announced a far-reaching opinion 
utterly at variance with Darwin’s view of the origin of the 
Galapagos. The great English scientist believed that the 
Galapagos were oceanic islands that had never been connected 
with the mainland —a view which Alex. Agassiz has supported 
after renewed study of the region. Dr. Baur rejected the 
hypothesis of the consistency of continents and oceans and 
asserted that the Galapagos, like the Antilles, were formed by 
subsidence and not by upheaval, and that they were at one 
time connected with Central America through Cocos Island. 
This contention Dr. Baur attempted to prove by showing that 
each separate island has its own peculiar and harmonious fauna 
and flora—a condition which could hardly exist if the archipelago 
were of volcanic origin and had acquired its plants and animals 
through accidental importation by means of currents from the 
mainland. Dr. Baur insisted on the harmonious distribution 
over the various Galapagos Islands of such organisms as the 
giant land tortoises, the lizards of the genus ‘Tropidurus, the 
species of Nesomimus and other passerine birds, and the plant 
known as Euphorbia viminea. Since there was no evidence 
_of intermigrations between the various islands to disturb the 
_ pronounced individual character of their faunas and floras, how 
