568 MEMOIRS OF THE NEW YORK BOTANICAL GARDEN 



burgk, in 1832, refers to "the sale of the underwood, which was 

 progressively cleared away, and which, being full of gum, had a 

 preference in the market of St. Thomas." 



There are apparently four endemic species in our collection, 

 these being an Acacia, forming a small tree, here described; a 

 Chamaesyce, pronounced by Dr. Millspaugh to be undescribed 

 (C. anegadensis Millsp. Field Mus. Bot. 2: 394. 1914); an Aste- 

 phaniis, regarded as new by Dr. Schlechter, and to be described 

 by him, and a new Arthonia, here described by Professor Riddle. 

 All the other species of our collection are found in one part or 

 another of the West Indies, none being characteristic of South 

 America, though many reach South America in their southward 

 distribution. That a number of the Anegada species do not 

 occur in the other Virgin islands was to have been expected, be- 

 cause there is no similar limestone area anywhere else in the 

 archipelago. 



No evidence former land connection of Anegada in any 

 direction has been adduced; all the species obser\^ed by us may 

 well have been brought there by oceanic or transoceanic distri- 

 bution. 



List of species 



Panicum geminatum Forsk. 



In a water hole near the settlement. St. Thomas: — Florida; 

 Bahamas; West Indies south to Martinique and Aruba; conti- 

 nental tropical America; tropical Asia and Africa. 

 Sporobolus argutus (Nees) Kunth. 



Border of marsh. St. Croix: — southern United States; Ba- 

 hamas; Jamaica; Cuba to Porto Rico; Bonaire; Curasao; Mexico. 

 Sporobolus virginicus (L.) Kunth. 



Border of marsh, Virgin Gorda; St. Jan; Tortola; Vieques: — 

 southeastern United States; Bermuda; Bahamas; West Indies; 

 continental tropical America; tropical Africa and Australasia. 

 Dactyloctenium aegyptium (L.) Willd. 



Waste grounds. Tortola; St. Jan; St. Thomas; Vieques; St. 

 Croix: — southern United States; Bahamas; West Indies; conti- 

 nental tropical America and Old World tropics. 

 Eragrostis ciliaris (L.) Link. 



Frequent on the rocky plain. X'irgin (jorda; Tortola; St. Jan; 

 St. Thomas; Culebrita; Vieques; St. Croix: — southern United 



