UNIVERSITY OF CALIFORNIA PUBLICATIONS 



IN 



BOTANY 



Vol. 6, No. 9, pp. 199-220 



Issued March 10, 1916 



FLOIJAL KELATIOXS AMONG THE 

 GALAPAGOS ISLANDS 



BY 

 A. L. KROEBER 



LmHAKV 

 NEW YOff^ 

 BOTANICAL 



UAKDBP^. 



In Professor B. L. Robinson's valuable and fundamental treatise 

 on the Flora of the Galapaj^os Islands/ he speaks repeatedly of the 

 many unexplained anomalies between the florulae of the various islands 

 of this .crroup, and concludes his mono<?raph by inferrinf^ from these 

 differencas and discrepancies that botanical evidence on the whole 

 opposes the theory of the formation of the islnnds by snbsidenef and 

 favors the hypothesis of their emergence. 



Of the species of Albemarle nearly half are common to Charles and Chatham, 

 and about one-third to James, while scarcely more than one-fifth have been 

 found on Indefatigable, although it attains about the same height and lies 

 directly between Albemarle and Chatham. 



Of its [Barrington's] 40 species, 26 occur upon Charles and Chatham 

 islands, while but 18 have been found on the nearer Indefatigable. 



More than half the plants of Bindloe occur upon Charles, Chatham, and 

 Albemarle respectively, while the proportion found on Abingdon and Tower 

 [nearer islands] is considerably less. 



It is another of the unaccountable anomalies in the florulae of these islands 

 that the common element between Duncan and Charles or Chatham is greater 

 than between Duncan and the nearer islands of Albemarle, Indefatigable, and 

 James. 



It is a curious fact that of the twenty-two plants observed on this island 

 [Jervis] only nine have been found on the adjacent James Island, although 

 twelve have been collected upon Chatham, and no less than fifteen on Charles,, 

 both much more distant. 



It is noteworthy that less than half the plants of the Seymour Islands 

 have as yet been found upon Indefatigable, near as it is; indeed the common 

 element is considerably greater with the much more distant islands of Charles, 

 Chatham, and Albemarle. 



1 Proc. Am. Acad. Arts and Sciences, 38, 77-269, 1902. 



