NOTES ON THE FORMS OF CASTELA GALAPAGEIA 
Alban Stewart 
According to the Index Kewensis, the genus Castela Turp. is 
composed of eleven species, which occur for the most part in Mexico, 
West Indies, and southern South America, the genus being thus dis- 
tinctly American in its distribution. One of these species, C. gala- 
pageia Hook, f., is peculiar to the Galapagos Islands and was described 
from material collected by Darwin when he visited the Islands on his 
voyage around the world as naturalist of the Beagle. Darwin collected 
his material on Chatham Island, and it was not known until nearly 
sixty years afterwards, when Baur visited the Galapagos Islands, that 
this species occurred on other islands of this group. Baur succeeded 
in finding this species on Albemarle, Bindloe, Charles, Chatham, 
Duncan, Jervis, and James Islands, and the collections made by him 
were studied by Robinson and Greenman^ of the Gray Herbarium of 
Harvard University. Eight years after Baur was on the islands, they 
were again visited by Snodgrass and Heller of the Hopkins-Stanford 
Expedition. Their collections of plants were the most corriplete that 
had been taken from the islands up to that time, but they succeeded 
in extending the range of C. galapageia to but one other island, viz., 
James. 
The collections of Snodgrass and Heller were studied by Robinson, 
who, aided by the additional specimens which this collection furnished, 
thought that he could recognize formal differences in the Castela 
material. He consequently described six new forms^ basing his 
differences mainly on the arming of the stem and the shapes of the 
leaves. The forms described by Robinson are: albemarlensis, binci- 
loensis, carolensis, duncanensis, jacobensis, and jervensis, the forms 
being named for the various islands respectively on which the type 
specimen of each was collected. 
1 was fortunate enough to secure much additional material of 
this species when I visited the Galapagos Islands in 1905-1906 as 
^ On the Flora of the Galapagos Islands as Shown by the Collections of Dr. Baur. 
Amer. Journ. Sci. III., 50: 135-149. 1895. 
2 Flora of the Galapagos Islands. Proc. Amer. Acad. 38: 77-269, pis. 1-3. 1902. 
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