TEREBINTHAOE^ 



263 



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

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

 foliolate, the polygamous flowers are usually tetramerous or diplo- 

 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 their insertion is 

 slightly perigynous." The fruit is 

 a drupe, 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 BoswelUa (fig. 280-283), 

 consisting of trees from the same 

 regions, the flower is usually pen- 

 tamerous with a trimerous gynse- 

 ceum. The petals, more or less 

 imbricate, and the diplostemonpus 

 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 three vertical 

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

 seen three stones, cordiform or echinate (fig. 383), each containing 

 a seed having a contortuplicate embryo with multifid cotyledons. 

 The leaves of BoswelUa are alternate and imparipinnate. 



In the Canarium, beautiful trees of all the tropical regions of the 



Kg. 277. Floriferous 

 branch. 



Kg. 279. Longi- 

 tudinal section of 

 male flower. 



• It is probably near Balsamea that we ought 

 also to describe Sasyoarya, given as a Spondias, 

 and having polygamous flowers, pentamerous, 

 ■with five petals, induplicate or slightly imbri- 

 cate, ten stamens, a gynseceum with three 

 biovulate cells, and a drupaceous fruit -with 

 trilocular stone. The exalbuminous seeds have 

 an embryo with an inflected superior radicle. 

 D. grisea is a tree with imparipinnate leaves and 

 flowers in axUlary spike-shaped clusters, in- 



habiting the mountains of Mexico. 



Faiveusea, a tree from Angola, unknown to 

 UB, is also brought near Protiitm ; it is distin- 

 guished by digitate leaves, capitate infloresenoe, 

 surrounded by an involucre, and apetalous uni- 

 sexual flowers, -with an inconsiderable calyx, 

 6-8-lobate, and a like number of stamens. The 

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

 ported by a long peduncle and surrounded by 

 an accrescent calyx. 



