SOAPBERRY FAMILY (SAPINDACEAE) 



142. Serrasuela 



This small tree or shrub restricted to dry south- 

 western Puerto Rico is distinguished by: (1) few 

 slender spreading branches and witliout a definite 

 crown; (2) leathery elliptic leaves simple (some- 

 times compoiuid with 3 leaflets), rounded at apex 

 and short-poLnted at base, the edges finely toothed, 

 shmy gre«n above and jjale green and densely soft 

 hairy with prominent veins beneath; (3) many 

 small whitish flowers Yie inch across, 4- or 5- 

 parted, in narrow branclied lateral clusters 1-21/4 

 inches long; and (4) brown narrow key fiiiits V2~ 

 % inch long, usually 3 attached together. This 

 species is closely related to the next species, c«boru- 

 quillo (Thouinla striata Radlk.), a large tree hav- 

 ing compound leaves with 3 thinner leaflets and 

 smaller flowere. Intermediate individuals have 

 been found. 



A deciduous tree becoming 15 feet high and 3 

 inches in trunk diameter. The gi"ay bark is rough, 

 fissured and divided into thin scaly plates. Inner 

 bark is brownish and slightly bitter. Twigs are 

 brownish green, finely hairy when yoimg, becom- 

 ing gray. 



The alternate leaves have finely brownish hairy 

 petioles %-lV2 inches long. The blade is iisually 

 simple and 2^ inches long and 1-2 inches wide, 

 the upper surface nearly hairless except on veins. 

 Sometimes there are 3 stalkless leaflets at end of 



Thouinia portoricensis Radlk. 



petiole, the 2 lateral leaflets much smaller, %~1V^ 

 inches long. 



The densely hairy flower clusters (thyi-ses) are 

 attached along the twigs, often at leaf bases. 

 Flowers are male, female, and bisexual (polyg- 

 amous), borne on short stalks less than Vs inch 

 long. There are 4 or 5 greenish haii-y sepals more 

 than i/ie inch long and rounded at apex; 4 or 6 

 white petals less than % inch long; 8 stamens % 

 inch long on a disk; and pistil i/g inch long with 

 hairy 3-celled ovai-y of 3 nearly separate lobes and 

 3-f orked style rising between lobes. 



The dry fruits (samaras), usually 3 developing 

 from a flower, are finely hairy, enclosed 1 seed at 

 base, and have a long narrow curved wing %e inch 

 wide. Flowering and fruiting nearly through the 

 year. 



The sapwood is light brown and hard. The 

 wood is little used. 



Forests and thickets of the dry limestone region 

 of southwestern Puerto Rico. 



Public forest. — ^Guanica. 



MuNICIPAHTIES WHERE ESPECIALLY COMMON. 



28, 38, 54. 



Range. — Confined to southwestern Puerto Rico. 



Other common name. — quebracho (Puerto 

 Rico). 



Botanical synonym. — Thyana portoricensis 

 (Radlk.) Britton. 



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