Vol. I] STEWART— BOTANY OF THE GALAPAGOS ISLANDS 9 



Unfortunately many of the former collectors of plants 

 remained but a short time upon the islands, and as most 

 of them were not botanists, our knowledge of the general 

 botanical conditions has remained rather meager. 



It was the intention at first to incorporate the entire botani- 

 cal results of the expedition in a single paper, but as the 

 present paper has assumed greater proportions than was 

 expected, it seems best to divide the subject and publish the 

 parts separately. The present paper consists of a rather 

 detailed account of the different species of vascular plants, 

 including their range in elevation and their distribution on 

 the different islands ; a brief description of the different botani- 

 cal regions; an account of the general features of the flora; 

 an account of the factors governing the growth of vegetation ; 

 and an account, so far as possible, of the evidence offered by 

 the collection concerning the origin of the islands and of the 

 flora. A second paper will deal entirely with a description 

 of the botanical conditions on each island of the group, and 

 short papers will treat of the lichens and mosses. 



The plan of treatment of the first part of this paper is in 

 general the same as that pursued by Robinson in his "Flora 

 of the Galapagos Islands," as I was unable to devise a plan 

 which I thought would be better. Many of the statistical 

 tables are simply revisions of the tables as given by Dr. 

 Robinson, although a few new ones have been added where it 

 seemed necessary. The entire nomenclature has been carefully 

 gone over and revised to make it conform with the new rules 

 of the Vienna conference. The ferns have been treated as 

 a single family and not split up into several different families 

 as has been done by some authors. Treating the group in 

 this manner has enabled me to handle it to better advantage 

 in the latter part of this paper. With but one exception the 

 nomenclature of Christensen, "Index Filicum," has been used 

 in this family. Unfortunately none of our instruments of 

 measurement were graduated with the metric system, other- 

 wise it would have been used. In order to economize space, 

 the names of former collectors are only mentioned where there 



