TREES OF PORTO RICO. 87 



Wood light-colored, fine-grained, moderately hard, heavy, and strong. Pores 

 minute, numerous, isolated or in groups of two or three, evenly distributed. Pith 

 rays numerous, minute, inconspicuous. 



118. Xylosma. 



Two species very similar as to their wood and uses and neither of any great impor- 

 tance are Xylosma schwaneckeanum Krug. & Urb. (= Myroxylon schwaneckeanum 

 Krug. & Urb.) (Palo de candela, Palo Colorado), and Xylosma buxifolium A. Gray 

 (= Myroxylon buxifolium Krug. & Urb.) (Roseta), trees from 15 to 35 feet high and 1 

 foot in diameter, the former found chiefly in the Lnquillo region and the latter through- 

 out the southwestern part of the island and the West Indies generally. The wood has 

 no uses except for fuel and charcoal. 



Wood light brown, turning darker with age, straight and fine-grained, hard, heavy, 

 strong, tough, and very durable in contact with the soil. Pores numerous, very small, 

 arranged singly or in short radial rows. Pith rays very narrow and inconspicuous. 



119. Casearia. 



Five species attain tree size, namely, Casearia guianensis (Aubl.) Urb. (Gafeillo, 

 Cafetillo, Palo bianco), from 15 to 30 feet high; Casearia bicolor Urb. (Talantron, 

 Cotorrerillo ?), 45 feet high; Casearia decandra Jacq. (Caracolillo, Cereza, Cotorrerillo, 

 Gia mansa, Palo bianco), from 18 to 25 feet; Casearia arborea (L. CI. Rich.) Urb. (GLa 

 verde, Rabojunco, Rabo raton), from 15 to 45 feet high; and Casearia sylvestris Sw. 

 (Cafeillo cimarron, Laurel espada, Sarna de perro), from 25 to 60 feet high. 



These trees are most common in the calcareous foothills and along the coast in all 

 parts of the island, except the last two, which are reported well distributed through- 

 out the interior mountains from the Sierra de Luquillo to Maricao and Mayaguez. 

 They are also widely distributed throughout the West Indies, except C. bicolor, which 

 is reported only from Porto Rico (Utuado). 



Wood of C. guianensis reported to be yellow, hard, and heavy (about G5 pounds per 

 cubic foot), and to be used for lumber, for building native huts, for fences, and for 

 similar uses. 



XXXVIII. Cactace^. 



120. Represented in Porto Rico by four genera (one exotic) and eight species (two 



exotic). 



These have an erect form and attain tree proportions, or at least are designated 

 "Pitajaya" (meaning tree-cactus) by the natives, although they do not all have a 

 true woody structure and are consequently not real trees, namely, Cereus quadrico- 

 status Bello (Pitajaya, Sebucan), from 6 to 30 feet high; Cereus triangularis (L.) Haw. 

 (Pitajaya); Cereus trigonus Haw. (=C. triangularis Stahl. C. & C) (Pitajaya), from 3 

 to 9 feet high; Cereus peruvianus (L.) Mill, a continental species from 15 to 25 feet 

 high, occasionally cultivated in gardens; Pilocereus royeni (L.) Rumpl. ( = Cereus 

 swartzii Stahl. C. & C.) (Sebucan), 9 feet high; Opuntia catacantha Lk. et Otto, 15 feet 

 high; Opuntia guanicana K. Schum. (Tuna), from 12 to 15 feet high; and Nopalea 

 coccinellifera (L.) Salm-Dyck (Tuna de Espana, Tuna mansa), a tropical American 

 and West Indian species 12 feet high, occasionally cultivated in gardens. 



Their natural distribution is limited largely to the semiarid south coast region, 

 including the small adjacent islands, as Culebra, etc., though they occasionally are 

 found on the limestone hills along the north side of the island. All, except C. quad- 

 ricostatus and Opuntia guanicana, which are strictly local in occurrence, are more or 

 less common to the other islands of the West Indies and tropical America. 



XXXIX. Th^ymel^eace^e. 



121. Daphnopsis. 



Two species attain tree size in Porto Rico: Daphnopsis caribaea Griseb. (Emajagua 

 de sierra), from 15 to 45 feet high, found chiefly in the Sierra de Cayey and Cordillera 

 Central and widely distributed throughout the West Indies; and Daphnopsis philip- 

 iana Krug et Urb. (Cieneguillo, Emajagua brava, Emajagua de sierra, Majagua 

 quemadora), from 8 to 25 feet high, occurring throughout the mountains from the Sierra 

 de Luquillo to the Cordillera Central. 



