272 



THE BEAN FAMILY. 



In the great majority of the species, forming the sub-family 

 Papilionaceae, the flower has the same general structure as 

 that of the Broad Bean. There are two other sub-families, 

 not represented in Britain ; one of these includes the Acacias 



and the Sensitive Plant 

 (Mimosa). The family 

 includes trees, shrubs, 

 creeping plants, climbing 

 plants, erect herbs, 

 annuals, and perennials ; 

 the leaves vary greatly in 

 form, etc. Examine all 

 the plants of this type 

 that you find growing wild 

 or in cultivation. 



The British Papiliona- 

 ecae may be divided into 

 five tribes. I. Gorse tribe : 

 leaf simple or of 2 or 3 

 leaflets, no tendrils, leaves 

 (or leaflets) with entire 

 margin. II. Clover tribe : 

 like I., but leaflets serrate. 

 III. Lotus tribe: leaf 

 with 2 or more pairs of 

 leaflets and an end-leaflet, 

 no tendrils. IV. Sainfoin 

 tribe: like III., but pod consisting of 1 or more inde- 

 hiscent one- seeded joints instead of opening by 2 valves. 

 V. Vetch tribe : leaf with the stalk ending in a tendril or 

 point. 



STIPULE 



STEM 



Fig. 97. Part of a Garden (Culinary) Pea 

 Plant (Pisum sativum). 



299. Gorse Tribe. 



A. Calyx deeply 2-lipped, coloured : Ulex (Gorse). 



B. Calyx shortly 2-lipped, green. 



1. Each calyx-lip deeply toothed : Genista (Petty Whin, Dyer's- 



weed). 



2. Each calyx-lip minutely toothed : Cytisus (Broom, Labur- 



num). 



