TEREBINTHA CE^ 



263 



Salsamea Opobalsamum. 



Fig. 278. 

 Male flower 



shrubs of tropical Africa, Asia and Oceania (fig. 277-279), having 

 branches often thorny, and alternate leaves, imioaripinnate or 1-3- 

 foliolate, the polygamous flowers are usually tetramerous or dijilo- 

 stemonous, and the gynseceum generally reduced to two carpels. 

 But these organs are nearly always 

 inserted on a slightly concave re- 

 ceptacle, lined by a cup-shaped 

 disk, so that theii* insertion is 

 slightl)^ perigynous. The fi.-uit is 

 a cbupe, with one or more stones 

 united together by the axis, and 

 an exocarp separating in two or 

 more valves. The seed contains an 

 embryo with contortuplicate cotyle- 

 dons.' In Bostvellia (fig. 280-283), 

 consisting of trees from the same 

 regions, the flower is usually pen- 

 tamerous with a trimeroiis gynse- 

 ceum. The petals, more or less 

 imbricate, and the diplostemonous 

 androceum are also insei-ted on a 

 very slightly concave receptacle, 

 and are, accordingly, somewhat perigynous. The fruit (fig. .'282- 

 283) has three projecting angles or three obtuse and thick wings. 

 On a level with these projections, the exocarp separates by vertical 

 clefts in three panels separating from the central portion of the fruit. 

 This then resembles a woody columella prolonged in thi'ee vertical 

 wings, corresponding to the intervals of the cells, between which are 

 seen thi-ee stones, cordiform or echinate (fig. 283), each containing 

 a seed having a contortuplicate embryo with multifid cotyledons. 

 The leaves of Boswellia are alternate and imparipinnate. 



In the Ccmarium^ beautiful trees of all the tropical regions of the 



Fig. 277. Floriferous 

 branch. 



Fig. 279. Longi- 

 tudinal section of 

 male flower. 



' It is probably near Bahamea that we ought 

 also to describe Daaycarya., given as a SponiVias, 

 and having polygamous flowers, pcntamerous, 

 with five petals, induplicatc or slightly imbri- 

 cate, ten stamens, a gynajceum with three 

 biovulate cells, and a drupaceous fniit with 

 trilocul.ar stone. The cxalbuminouB seeds have 

 an embryo with an inflected superior radicle. 

 D. gristtt is a tree with imparipinnate leaves and 

 flowers in axiUary spike-shaped clusters, in- 



habiting the mountains of Mexico. 



Faivetisea, a tree from Angola, unknown to 

 us, is also brought near Protiiim ; it is di.'itin- 

 guished by digitate leaves, capitate infloresence, 

 suiToimded by an involucre, and apetalous uni- 

 sexual flowers, with an inconsiderable calyx, 

 C-8-lobate, and alike number of stamens. The 

 fruit is a drupe with one or two stones, sup- 

 ported by a long peduncle and sui'rounded by 

 an accrescent calyx. 



