12 FLORA OP ST. CROIX AND THE VIRGIN ISLANDS. 



Centroserna, Terainnus, Vigna, Rhynchosia, and others; grasses, as Lap- 

 pago, Aristida, Sporobolus, Eleusine, Dactyloctenium, and Eragrostis ; 

 or Synanthereoe, as Elephantopus, Distreptus, Eidens, and Pectis. Whilst 

 all these latter forms flower daring the greater part of the year, the beau- 

 tiful Convolvulacese, such as Ipomcea fastigiata, Nil, umbellata, dissecta, 

 violacea, and others, are in blossom only during the winter months, from 

 December to February. 



In some places that are moist enough, sedges and semi-aquatic plants 

 will be seen growing ; in a few rivulets which contain water all the year 

 round, and which are limited to Vieques and St. Croix, a few aquatic 

 forins occur, such as Ecliinodorus cordifolius, Lemna minor, Typlia an- 

 gustifolia, and Nymphcea ampla. 



The pastures, which occupy a considerable extent of the land, are 

 either artificial, planted with Guinea-grass (Panicum maximum), a 

 jierennial plant, and, like most of the cultivated West India plants, in- 

 troduced from the Old World, or natural, covered with various forms of 

 indigenous Graininese as well as low shrubs and trees, that have con- 

 tinually to be cleared away to prevent the land becoming overrun by 

 them. The artificial pastures as a rule are fenced in, and often protected 

 against the dry season by the planting of Thibet-trees (Acacia Lebbcl),now 

 commonly naturalized everywhere; the natural ones, on the contrary, are 

 generally open and abandoned to the cattle, whilst the artificial oues are 

 cut regularly, and the stock is not allowed to enter them. 



The grasses composing the natural pastures are several species of Pa- 

 nicum, Paspalum, Dactyloctenium, and Sporobolus; some, as Tricholccna 

 insularis, being very bitter and unfit for herbage. The roaming about 

 of the cattle everywhere effectually prevents the re-establishment of trees 

 or woods, which, for climatic reasons, would be desirable in many places; 

 for the young buds are destroyed by sheep and goats, which no doubt 

 have contributed largely to deteriorating even the still existing woods. 



Around dwellings are found planted and naturalized most of the plants 

 now common to nearly all tropical countries, some fruit-bearing, as 

 Tamarindus indica, Mangifera indica, Carica Papaga, Persea gratissima, 

 Crescentia Cujcte, Melicocca bijuga; others ornamental, as Poinciana rcgia, 

 CalUandra saurian, Casalpinia pulchcrrima, and others Actual gardens 

 are now very rare, flowers being mostly cultivated in pots or boxes. 

 Some few vegetables of colder clmiates are cultivated in shady places 

 where water is abundant, such as salad, radishes, cabbage, and others. 



In waste places are found most of the tropical weeds, as Ricimts com- 



