ZYGOPHYLLACEiE. SILVA OF NOliTU AMERICA. 59 



GUAIACUM. 



Flowers perfect, terminal, solitary or umbellate- fascicled ; calyx 5 or rarely 

 4-lobcd, imbricated in aestivation, deciduous ; petals as many as the lobes of the calyx, 

 imbricated in aestivation, hypogynous ; stamens hypogynous, the filaments naked or 

 squamate. Fruit fleshy, 2 to 5-celled, dehiscent ; albumen corneo-cartilaginons, rimosc. 

 Leaves abruptly pinnate. 



Guaiacum, Linnffius, Gen. 140. — A. L. de Jussieu, Gen. Porlieria, Ruiz & Pavon, Prodr. 55, t. 9. — MeUner, Gen. 



296. Adanson, Fam. PL n. 507. — Endlicher, Gen. 59. — Endlicher, Gen. 1164. — Bentham & Hooker, Ge/i. 



1164. — Meisner, Gen. 59. — Gray, Gen. III. ii. 121 ; i. 268. 



Ptoc. Am. Acad, n, ser. xxii. 306. — Bentham & Hooker, 

 Gen. i. 267. — BaiUon, Hist. PI. iv. 608. 



Trees or shrubs, with white scaly bark, stout terete ahernate branches often with swollen nodes, and 

 hard resinous wood. Leaves petiolate, opposite, abruptly pinnate, with two to fourteen entire reticulate- 

 veined leaflets, and mmute more or less deciduous stipules. Flowers pedunculate from the axils of 

 minute deciduous bracts, blue or purple. Sepals slightly united at the base, unequal. Petals broadly 

 obovate, more or less unguiculate. Stamens ten, inserted on the short inconspicuous or elevated di^k 

 opposite to and alternate with the petals ; filaments filiform, naked or bearing at the base on the inner 

 surface a minute membranaceous scale ; anthers oblong, fixed near the base, introrsc, two-celled, the cells 

 opening longitudinally. Pistil of two or five united carpels ; ovary raised on a short thick stalk, obo- 

 vate or clavate, two to five-Iobed and two to five-celled, contracted into a slender subulate acute style ; 

 stigma minutely two to five-toothed or entire ; ovules eight to ten in each cell, suspended in pairs from 

 its inner angle by a slender funiculus, anatropous ; the raphe ventral. Fruit smooth, coriaceous, nar- 

 rowed at the base into a short stem, with two to five wing-like angles, ventially and sometimes dorsally 

 dehiscent. Seeds solitary or sometimes in pairs in each cefl, suspended, ovoid ; testa thick and fleshy, 

 easily separating from the hard bony nucleus closely invested with a thin Indistmct tegmen Embryo 

 straight or nearly so ; cotyledons oval, f oliaceous, incumbent or sometimes accumbent to the axis ot 



the fruit ; radicle short, superior.' 



The genus Guaiacum, extended to include Porlieria, is found in the West Indies, m the countries 

 adjacent to the Caribbean Sea and the gulfs of Mexico and CaKfornia, and in the Andes of Peru. Bot- 

 anists have distinguished about eight species, although further explorations in southern Mexico and in 

 Central America, .vhere seem to be the headquarters of the genus, may be expected to increase he ninn- 

 ber. The two ' species first known occur in the West Indies. One of these reaches the South Ameri- 

 can continent, and the other the keys of southern Florida and the Bahama Islands, the most northern 

 stations of the genus. One species ^ is found in western Texas and the adjacent regions of Mexico, 



^ A.. G», .as pointed out (P. Wri.M. i. 28. - S,ni.,.onian well as ps„ta.e™.s. ^lon (^"'~»"°; -^^^r"'' "^'"" 



Con.rU.. in.) that the position of the cotyledons of PorUeria ^^c. the san,e conclusion, and united ^f "; '■^"2^7;„„^,„„ ^in- 



».*,•», Ruiz & Pavon, is not uuiforn., that they are occasionally in- = G™— -i'-^"^'- 1— ■ ^^^ "^^^ ''"'»"""" "'"*'"' 



cumhent in G^fac™ .ffidnaU, L. (ft«. Ara. Acad. n. ser. zxii. ^...Spec. ^^'- Engehnann, Wi.lize«.s Mano.r of a 



306), and that the squamiferous filaments depended on to separate » G.<..» »'» °"»" '■^°''"'"' „ f^ ^„, 548), Bol. Appx. 113. - 



Porlieria from Gnaiacmu are sometimes found in hoth genera, while Tour in Northern Menco^(S.nate Doc. im>), PI 



the flowers ot Guaiacum parmjlorum are sometimes tetramcrous as Gray, Oen. III. 11. 12 , . 



