JOHNSTON: FLORA OF MARGARITA ISLAND. 297 



that of a tropical seashore, and is similar to that of Tortuga and Coche 

 and the coast of Margarita, though more limited. As reported by 

 Ernst there are twenty-four different species, of which Cyperus 

 hrunneus, Cyperus caesius, Eragrostis prolifera, and Opuntia spino- 

 sissima have not been reported from either Margarita or Coche. Two 

 of these, Cyperus caesius and Opuntia spinosissima, are not found on 

 Tortuga. It will be noticed, however, that these are of wide dis- 

 tribution. 



The three western islands l^'ing off the coast of Venezuela belong 

 to the Dutch Republic. The most important work that has been 

 done upon them botanically was by Suringar ('86). He lists, however, 

 scarcely a dozen plants from Aruba and Buen Ayre. From the 

 character of these two islands one is led to expect a flora similar 

 to that of Cura9oa though more limited. Buen Ayre is about forty 

 kilometers (25 mi.) east of Cura^oa and has an area of twenty-four 

 thousand hectares (85 sq. mi.), while Aruba is nearly seventy kilo- 

 meters west of Cura9oa with an area of seventeen thousand hectares 

 (69 sq. mi.). 



Cura^oa is the one of this group upon which some botanical work 

 has been done. Several botanists have \dsited the islands, the most 

 notable of whom was perhaps Suringar. As determined from his 

 list of Cura9oan plants (117 species), fifty have not been reported 

 from Margarita. To be sure Suringar's list is not taken to be at all 

 complete of the flora of Cura9oa. Simons ('68) has published a much 

 longer list but unfortunately the names are in a great part old ones and 

 quite impossible to identify for certain with those at present in use. 

 Even considering this list, Margarita has over four hundred plants not 

 on Cura^oa. This difference in the flora is due to marked contrast in 

 physical conditions and to their difference in geographical position. In 

 physical condition Cura^oa resembles the plains and hills of Margarita, 

 and has a vegetation similar to theirs, but the heavy woods and the 

 varied vegetation of the mountain tops are to be found in Margarita 

 only. In geographical position, although they are both coastal islands 

 and are on nearly the same parallel, yet they are five hundred kilo- 

 meters (300 mi.) apart and Cura9oa is ninety kilometers (50 mi.) from 

 the coast of Venezuela. It is probable that complete exploration of 

 both islands would show more resemblances between them, but 

 according to present knowledge, the differences in physical conditions 

 and in geographical situation alone may well account for the differences 

 in the floras. 



