THE APETALOUS ORDERS. 



473 



bract. Stamens definite. Ovary two-celled, each cell with one 

 suspended ovule : styles or stigmas distinct. Fruit membrana- 

 ceous or samara-like, one-celled and one-seeded, forming with the 

 three-lobed bracts a kind of strobile. Albumen none. Ex. Be- 

 tula (the Birch), Alnus (Alder). The bark is sometimes astrin- 

 gent, and that of the Birch is aromatic. The peculiar odor of 

 Russia leather is said to be owing to a pyroligneous oil obtained 

 from Betula alba. 



1056 



881. Ord, Salicaceft (the Willow Family). Trees or shrubs, with 

 alternate simple leaves, furnished with stipules. Flowers dioe- 

 cious ; both kinds in aments, and destitute of floral envelopes (ach- 

 lamydeous), one under each bract. Stamens two to several, some- 

 times monadelphous. Ovary one-celled, many-ovuled ! Styles or 

 stigmas two, often two-cleft. Fruit a kind of follicle opening by 

 two valves. Seeds numerous, ascending, furnished with a silky 



FIG. 1018. Amcnt of staminate flowers of Betula fruticosa ? 1049. One of the three lobed 

 scales of the same enlarged, showing the flowers (stamens) on the inner side. 1050. Ament of 

 pistillate flowers. 1051. Branch in fruit. 1052. One of the scales with its three flowers (pis- 

 tils) seen from within. 1053. Magnified section of one of the two-celled pistils, displaying the 

 ovule suspended from the summit of each cell. 1054. The pistils (with their subtending bract) 

 in a more advanced state. 1055. Magnified cross-section of one of the ovaries. 1056. The ma- 

 ture fruit, with the cell divided vertically; the single seed occupying the cavity; a mere trace 

 of the other cell being visible. 1057. The seed removed. 1058. The embryo. 



40* 



