472 SYSTEMATIC BOTANY. 



peculiar bracts, which become hooded, pouched, or spurred. They 

 are distinguished from Hypericaceae, chiefly by their unsymme- 

 trical flowers, equal-sided petals, distinct stamens, and sessile 

 stigmas. 



Distribution, Sfc. — Grenerally natives of equinoctial America. 

 Examples of the Genera: — Ruyschia, Marcgravia. There are 26 

 species. 



Properties and Uses. — Scarcely anything is known of their 

 properties. Marcgravia umhellata is reputed to be diuretic and 

 anti syphilitic. 



Natural Order 39. Rhizobolace^. — The Souari-nut Order. — 

 Character. — Large trees. Leaves opposite, coriaceous, digi- 

 tate, exstipulate, with an articulated stalk. Sepals 5 or 6, more 

 or less coherent, imbricated. Petals 5 to 8, unequal. Stamens 

 very numerous, slightly monadelphous, in two whorls, the inner 

 shorter and often abortive, inserted with the petals on a hypo- 

 gynous disk ; anthers 2-celled with longitudinal dehiscence. 

 Ovary 4, o, or many-celled ; styles short, as many as the cells 

 of the ovary ; stigmas small ; ovules solitary, attached to the 

 axis. Fruit consisting of several combined indehiscent 1-seeded 

 nuts. Seed reniform, exalbuminous, with the funicvilus expanded 

 so as to form a spongy excrescence ; radicle very large, form- 

 ing nearly the whole of the nucleus ; cotyledons very small 

 {Jig. 752). 



Diagnosis. — Large trees, with opposite digitate exstipulate 

 leaves, with an articulated stalk. Flowers regular, hypogynous. 

 Petals equal-sided, and inserted with the numerous stamens into 

 a hypogynous disk. Styles very short. Seed solitary, exal- 

 buminous, with a very large radicle, and two small cotyledons. 



Distribution, <^'c. — The order contains but 2 genera, including 

 8 species, all of which ai'e large trees, natives of the forests in 

 the hottest parts of South America. Examples of the Genera:—' 

 Caryocar, Anthodiseus. 



Properties and Uses. — Some of the trees are valuable for their 

 timber. Others yield edible nuts, and some an excellent oil. 

 The most important plant is the 



Caryocar hutyrosum {Pekea tuberculosa or hulyrosa) ; this is much esteeraed 

 for its timber, wiiich is used in ship-building and for other pm-poses. The 

 separated portions of the fruit constitute the Souari, Surah wa, or Suwarrow- 

 nuts of commerce, the kernels of which are probably the most agreeable of 

 all the nut kind. They are occasionally imported into this country. An 

 excellent oil may be also extracted from them. 



Natural Order 40. Sapindace^. — The Soapwort Order. — 

 Character {figs. 891-893). — Usually large trees ov twining 

 shrubs, or rarely climbing herbs. Leaves generally compound 

 {fig. 342), rarely simple, alternate or sometimes opposite, often 

 dotted, stipulate or exstipulate. Flowers {figs. 891 and 892) 

 mostly perfect and unsymmetrical, sometimes polygamous. 



