62 FOUNDATIONS OF BOTANY 



1. M. aurantiaca, Nutt. OsaoeOuange. A small tree with ridged, 

 yellowish-brown bark. Leaves minutely downy when young, becom- 

 ing smooth and shining with age, ovate or ovate-oblong, taper- 

 pointed at the apex, obtuse or subcordate at the base, entire, petioled. 

 Staminate racemes about 1 in. long. Pistillate flower clusters about 

 1 in. in diameter. Fruit yellowish, tubercled, 3-4 in. in diameter. 

 In rich soil. Native in Texas and extensively planted for hedges. 

 Wood very durable when exposed to the weather, and therefore used 

 for fence posts. As the wood does not swell or shrink with changes 

 in its moisture, it is highly valued for wheel hubs, etc.* 



ra. BHOUSSONETIA, L'Her. 



Small trees with milky juice. Leaves alternate, petioled ; 

 flowers dioecious. Staminate in cylindrical spikes, with a 

 4-cleft calyx, 4 stamens, and a rudimentary ovary. Pistil- 

 late flowers in capitate clusters. Calyx 3— 4-toothed. Ovary 

 stalked, style 2-cleft, fruit in a globular head.* 



1. B. papyrifera, Vent. Paper Mulberry. A round-topped tree 

 with yellowish-brown bark. Leaves cordate, often irregularly 2-3- 

 lobed, serrate, rough above, downy beneath, long-petioled. Stami- 

 nate spikelets peduncled, 2-3 in. long. Pistillate heads stout, pedun- 

 cled, about 1 in. in diameter. Introduced from Asia and very 

 common S. about old dooryards.* 



rV. CANNABIS, Tonm. 



Coarse herbs with very tough, fibrous bark. Leaves usu- 

 ally opposite, palmately compound. Flowers small, dioecious, 

 greenish, the staminate ones in compound racemes or panicles, 

 the pistillate ones in spikes. Calyx of the staminate flowers 

 of 5 sepals, that of the pistillate flowers of 1 large sepal 

 which covers the ovary and the akene. 



1. C. sativa, L. Common Hemp. An erect plant, 4-8 ft. high. 

 Leaves large, petioled, of 5-7 lanceolate, irregularly serrate or 

 toothed leaflets. Cultivated from Europe, S. and W., for its fiber, 

 and sometimes runs wild along roadsides in rich soil. 



21. trRTICACE.ffi;. Nettle Family. 



Herbs with watery juice, stem and leaves often clothed 

 with stinging hairs. Leaves undivided, stipulate. Flowers 



