DICOTYLEDONES : POLYPETALJ) : CALYCIFLORJ). 635 



true Service-Tree, and P. torminalis, the Wild Service-Tree : the sub-genus 

 Aria, includes P. Aria, the White Beam. The genus Amelanchier includes 

 the European A. vulgaris, and A. canadensis, the June Berry. The genera 

 Kaphiolepis and Photinia (incl. Eriobotrya, the Loquat), include well-known 

 cultivated flowering shrubs. 



There are two other tribes of exotic Bosaceae, the Quillaieas, and the Chryso- 

 balaneas, concerning which it is impossible to go into detail ; in the latter the 

 gynasceum, which is monomerous as in the Prune, is peculiar in that the 

 style is gynobasic ; and in some of the genera (Hirtellinae), the flower is 

 irregular and zygomorphic. 



Order 2. LEGUMINOSJ:. Flowers usually dorsiventral, perigy- 

 nous. pentamerous, with calyx arid corolla : stamens ten or more : 

 ovary of a single anterior carpel ; ovules borne on the ventral 

 suture: fruit a legume or a lomenturn: flowers always lateral: 

 leaves nearly always compound. 



The Leguminosae, more particularly the Papilioneas, are remarkable physi- 

 ologically by the presence of tubercles on their roots, caused by^thejtttack .of a 

 Fungus, and by their extraordinary faculty of flourishing in soils poor in com- 

 bined nitrogen : these two facts are un- 

 doubtedly correlated, but the exact nature 

 of the correlation is still a matter of dis- 

 cussion (see Part IV.). 



Sub-order 1. PAPILIONE^E. Flowers dorsi- 

 ventral, papilionaceous (Fig. 327 A). The 

 five sepals, the odd one being anterior, are 

 usually connate, forming a tube above the 

 insertion of the corolla and the androecium : 

 the five lobes are usually unequal and 



sometimes form two lips, the lower of three 



FIG. 435. Flower of Lotus cwnicu- 

 and the upper of two teeth : petals five, latus ( 80mewbat mag . )> A with one 



alternate with the sepals, imbricate so that a la removed ; k calyx; fa vexillum; 

 the anterior petals are overlapped by those jiala; s carina. B With the corolla 

 behind them ; the posterior petal is much removed ; r tube formed by the nine 



enlarged, and is called the vexillum (Fig. stame s ' ' the free 8tamen an ' 



ther ; n stigma. 

 435 A fa) ; the two lateral petals, which 



are much smaller, are termed the ala (Fig 435 A, fl) ; the two anterior petals 

 are connate or sometimes simply apposed, and form a hollow boat-shaped body, 

 the keel, or carina (Fig. 435 A, s). In a few cases the corolla is entirely or 

 partially suppressed ; thus in Amorpha, only the vexillum is present. The ten 

 stamens belong to a single whorl, with direct diplostemony ; they are either 

 connate and monadelphous, forming a tube, or the posterior stamen may be free, 

 so that the tube consists of nine stamens, and is incomplete posteriorly (Fig. 435 

 J5), in which case the androecium is diadelphous (9-1) ; rarely the stamens are 

 all free ; they mostly curve upwards, and diminish in length from in front back- 

 wards. The ovary, enclosed by the staminal tube, consists of a solitary anterior 

 carpel ; it is often diuded into chambers by a spurious longitudinal septum, or 



