PHANEROGAMIA 



555 



alternately. Stipules wanting. Male catkins springing from the 

 leaf-axils of twigs of the preceding year ; female flowers in terminal 

 spikes containing more or less numerous flowers; Ovary inferior. 



The Wahmt, Juglans regia (Fig. 559), is the best-known representative of the 

 family. It is endemic in Western Asia and the eastern portion of the Mediter- 

 ranean region, but the tree is in cultivation throughout Europe. In spring the 

 axillary buds of the previous season produce long, thick, pendulous catkins bearing 

 numerous flowers. Each of the latter has 3 to 5 perianth segments, and these together 

 with the two bracteoles are adherent to the bract and surround the numerous 

 stamens, which face towards the tip of the inflorescence. The female flowers in 

 smaller numbers are borne at the summit of the young shoots. The two carpels 

 terminate in large, feathery, diverging stigmas. The perigone is adherent to the 

 bract and bracteoles and reaches to the summit 

 of the inferior ovary. The single loculus encloses 

 an atropous, basal ovule. Fruit, a drupe. The 

 exocarp contains abundant tannin. The hard 

 endocarp is divided into two valves in the plane 

 of the dorsal sutures of the coherent carpels, the 

 limits of which are indicated by the partial septum 

 at the lower part of the fruit. Within the stone 

 is the embryo, enclosed in a thin seed-coat. The 

 large cotyledons, which contain oil, are lobed 

 in correspondence with the false septa that pro- 

 ject from the inner surface of the ovary. Endo- 

 sperm wanting. Other species of Juglans and 

 Carya yield edible seeds and valuable timbers. 



Family 2. Myricaceae. Myricn gale is a 

 dioecious shrub with entire leaves found on moors. 

 Some American forms yield wax derived from the 

 fruits (p. 101). 



The family of the Casuarinaceae, the syste- 

 matic position of which is doubtful, may be 

 mentioned here. They are trees growing by the 

 sea-shore or on mountains, and are distributed 

 from southern Asia and Australia throughout 

 the Polynesian islands. Chalazogamy ( u ) was 

 first discovered by Treub in Casuai-iim. 



Order 3. Salieiflorae 



Family Salicaceae. Trees and shrubs 

 with simple, alternate, stipulate leaves. 

 Flowers in dioacious catkins, usually 

 developed before the leaves. Both male 

 and female flowers are naked and stand 

 in the axils of bracts. More or less de- 

 veloped scale-like development of the disc 

 or floral receptacle. Ovary of two carpels, 

 unilocular. Fruit, a capsule containing 



H 



FIG. 560. Zaliz viminaltf. A, Flower- 

 ing male twig (nat. si/e) ; IS, male 

 flower with sutitcndiiij; l>i"ict (mo- 

 llified); i', female inflorescence; 

 !>!:, female tlmvers (ma-nilied) ; F, 

 fruit (nat. size) ; G, the same mag- 

 nified ; //, seed (magnified). 



