TREES WITH HIGHLY-DEVELOPED FLOWERS 303 



distinct internodes, while those on the dwarf shoots arise in 

 tufts (Fig. 201, 3). The leaves are alternate and compound ; 

 the base is small with narrow persistent stipules ; the 

 petioles are long, and the blade is trifoliate. Each 

 leaflet is attached by a short stalk, and is entire, ovate, 

 and pointed ; the upper surface is smooth ; the under 

 surface silky white, especially when young. 



The inflorescence is a lax drooping raceme (4). The 

 flowers are irregular, pea-like (papilionaceous), and open 

 in May. The calyx is two-lipped and consists of five 

 united but unequal sepals. The corolla has five petals, as 

 in the Sweet-Pea. The drooping habit of the raceme 

 inverts the flowers. This, however, is righted by the 

 twisting of the young flower-stalk (5), and thus the 

 standard is brought into its usual conspicuous and erect 

 position (6). The honey is quite concealed and secreted 

 in a swelling at the base of the standard, which has two 

 dark honey-guides directed towards the nectary. The 

 receptacle is slightly hollowed, and the petals and also the 

 stamens are joined to the side of it, being therefore peri- 

 gynous (7). The ten stamens are all joined (monadelphous) 

 (8), and are ripe before the stigma. The pistil has only 

 one carpel ; and the style, together with the stamens, is 

 upturned in the keel. 



The flowers are visited by bees, and after each visit the 

 keel springs back into its place ready to be revisited. The 

 fruit is a pod, constricted between the seeds and covered 

 with dark brown hairs. The seeds and other parts of the 

 tree are poisonous. 



Sycamore 



The Sycamore (Acer Pseudo-platanus) (Fig. 202) is a 

 native of Middle Europe, but not of Britain. It is, however, 

 a very familiar tree in woods, parks, and hedgerows. Often, 

 when the Oak is cut down in the woods, the Sycamore is 



