524 



THE NATURE BOOK 



opposite pairs, each next succeeding 

 pair being at right angles to that preceding. 

 Tliis will be found conclusive in distinguish- 

 ing, at an\' season, a Maple from a Plane, on 

 which the arrangement of the buds is alter- 

 nate. The ty-pical Maple leaves are five- 



nor nectar. Moreover, its flowers are 

 chstinct. the pollen- bearing from the 

 fruit-producing, and grow on separate 

 trees. The Sycamore's flowers of both 

 kinds grow together in a single drooping 

 cluster, and each flower has small green 



i 



i 

 I 



SYCAMORE IN WINTER. 



lingered, after the manner of those of the 

 Plane ; they have five main divisions, each 

 possessing a separate main rib, proceed- 

 ing from the point of junction with the 

 stalk, and terminating at the apex of its 

 own leaf division. The leaf of the Box 

 Elder is not simple, but com])ound. after 

 the manner of the Ash or the Elder, hence 

 this tree's alternative names. This com- 

 pound leaf has usually five (sometimes 

 three only) indi\-idual leaflets. The flowers 

 of the Maples have special interest for us 

 in that they afford a striking illustration 

 of the different stages intervening between 

 the wind-pollinated flowers witliout petals 

 or nectar, and the insect-ptjllinated fl(nvers 

 with nectar and rendered more conspicuous 

 by petals. The Box Elder is entirely 

 wind-pollinated, and has neither petals 



petals and store of nectar. The Field 

 Maple has similar flowers, but these are 

 grouped in erect, more open clusters, 

 with petals relatively somewhat larger, 

 and yellowish green in colour. The 

 Norway Maple has larger, erect and closer 

 clusters, with larger yellow petals — much 

 more conspicuous, and rendered more so 

 still from the fact that the flowers open 

 before the leaves expand. The fruits 

 grow in pairs, as winged seeds, joined at 

 the base. In their dispersal these winged 

 seeds come apart, each as it is borne away 

 by the wind spinning vigorously. They are, 

 in fact, something between a parachute 

 and an aeroplane, and are capable of 

 travelling a considerable distance with the 

 wind. Tlie angle or otherwise which 

 these paired and winged fruits take in 



