SYCAMORE: NORWAY MAPLE 295 



(/3) Disc conspicuous as a fleshy hypogynous 

 ring, on which the stamens are inserted. 

 Flowers in racemes, corymbs or panicles. 

 * Ovary of two winged and flattened carpels, [For (**) 

 style one, stigmas two : sepals and petals se 

 5 each, stamens 8. 



t Flowers in pendent racemes ; juice not milky. 

 Acer pseudoplatanus, L. Sycamore (Fig. 114). Tree, 

 with opposite palmatifid leaves. 



Floral formula K 5 C 5 A 4 + 4 0(2). Flowers protan- 

 drous, with exposed honey. Flowers in pendent stalked 

 racemes of umbellate cymes of about 3 each ; opening after 

 the inflorescence is complete, each on a rather long pedicel. 

 Each terminal or central flower in the cyme usually 

 hermaphrodite, the lateral male, with longer stamens 

 and abortive pistils. Sepals and petals nearly alike, 

 greenish-yellow. Stamens hairy; ovary tomentose. Pollen 

 ellipsoid-fusiform, with 3 longitudinal bands and numerous 

 striae. Fruit pendent, glabrous, the two long green wings 

 directed forwards and often nearly parallel to the fruit- 

 axis. 



ft Flowers not in pendent racemes but in 

 corymb-like panicles of cymes; sap milky. 



Wings of fruits divaricating at angles of 

 5060 with the axis. 



Acerplatanoides, L. Norway Maple (Fig. 115). Tree 

 like the last, but the lobes of the leaves more drawn out 

 and angular. 



Flowers in erect panicles of cymes, opening early, before 

 the foliage expands, yellowish-green. Most of the earliest 

 flowers are ? , the later </ by abortion. Honey exposed. 

 Stamens of the male flowers as long as the petals. Pollen 

 elongated, pale yellow, about 50 x 25 /z, with 3 longitudinal 



