BRIXTON: THE VEGETATION OF ANEGADA 579 



St. Thomas; St. Croix; Vieques :— Florida ; Bermuda; West Indies; 



Mexico; tropical Africa. 



GuNDLACHiA CORYMBOSA (Urban) Britton. 



Abundant on the sandy plain, West End. Bahamas; Porto 

 Rico to Guadeloupe; Curasao. Not known from the other 

 Virgin Islands, but found on Saba. 

 Pluchea purpurascens (Sw.) DC. 



Moist places on the rocky plain. St. Thomas; St. Croix: — 

 southeastern United States; Bermuda; West Indies, south to 

 Guadeloupe; continental tropical America. 



BORRICHIA ARBORESCENS (L.) DC. 



Abundant in salinas. West End. St. Thomas; St. Croix; 

 Culebra; Vieques: — southeastern United States; Bermuda; West 

 Indies and continental tropical America. 

 Wedelia parviflora L. C. Rich. 



Frequent on the rocky plain. Tortola; St. Jan; St. Thomas; 

 St. Croix; Vieques; Culebra: — Porto Rico to Trinidad. 

 Bryum microdecurrens E. G. Britton. 



On the rocky plain near the settlement. Mona. 

 Hymenostomum Breutelii (C. Muell.) Broth. 



On the rocky plain near the settlement. Tortola; St. Jan; St. 

 Thomas. 

 Chara. 



In a water hole near the settlement. 



Lichens 

 (Determined by Professor Lincoln W. Riddle.) 

 Arthonia interducta Nyl. 



On Acacia anegadensis . 

 Arthonia anegadensis Riddle, sp. nov. 



Thallus epiphloeodes crustaceus sat crassus rimulosus laevi- 

 gatus niveus. Apothecia dispersa, rotundato-difformia aut sub- 

 elongata, diam. 0.2-0.5 mm., primum immersa vestitaque demum 

 aperta thallum subaequantia, disco piano epruinoso, sicco nigro, 

 madefacto badio, materias KOH reagentes haud continents. 

 Epithecium fulvum; hymenium et hypothecium decoloratumj 

 hymenium iodo vinose rubens. Asci late ovales, octospori. 

 Sporae decolores vel subfuscescentes, oblongae, 6-loculares, cellulis 

 subaequalibus, 15-18 ju X 5-6 M- 



