URTICACEAE (XETTLE FAMILY) 347 



taper-pointed^ rounded at base, mostly oblique, thin, and smooth ; fruit small. 



— Chiefly in rich bottom-lands, s. Ind. to Mo. (Bush), and s. to Fla. and Tex, 



— A small tree with warty bark. (Mex., Bermuda.) 



4. CANNABIS [Tourn.] L. Hemp 



Flowers green ; the sterile in axillary compound racemes or panicles, with 5 

 sepals and 5 drooping stamens. Achene crustaceous. Embryo simply curved. 



— A tall roughish annual, with digitate leaves of 5-7 linear-lanceolate coarsely 

 toothed leaflets, the upper alternate ; the inner bark of very tough fibers. (The 

 ancient Greek name, of obscure etymology.) 



1. C. SATivA L. — Waste and cultivated ground. (Adv. from Asia.) 



5. HAMULUS L. Hop 



Flowers dioecious ; the sterile in loose axillary panicles, with 5 sepals and 

 5 erect stamens. Fertile flowers in short axillary and solitary spikes or catkins ; 

 bracts foliaceous, imbricated, each 2-flowered, in fruit forming a sort o^ mem- 

 branaceous strobile. Achene invested with the enlarged scale-like calyx. Em- 

 bryo coiled in a flat spiral. — Twining rough perennials, with stems almost 

 prickly downward, and mostly opposite heart-shaped and palmateiy 3-7-lobed 

 leaves. (A late Latin name, of Teutonic origin.) 



1. H. Lupulus L. (CoMMOx H.) Leaves mostly 3-5-lobed, commonly longer 

 than the petioles ; bracts, etc.. smoothish ; the fruiting calyx, achene, etc., 

 sprinkled icith yellow resinous grains, which give the bitterness and aroma to 

 the hop. — Alluvial -banks, rubbish heaps, etc., common. July. (Eurasia.) 



2. H. JAPoxicus Sieb. & Zucc, with smaller more deeply 5-Iobed leaves and 

 herbaceous bracts without glandular atoms, occasionally escapes from frequent 

 cultivation. (Introd. from Japan.) 



6. MACLURA Nutt. Osage Orange. Bois d'Arc 



Flowers dioecious ; the staminate in loose short racemes, with 4-parted calyx, 

 and 4 stamens inflexed in the bud ; the pistillate in a dense globose head, with 

 a 4-cleft calyx inclosing the ovary. Style filiform, long-exserted ; ovule pen- 

 dulous. Fruit an achene. buried in the greatly enlarged fleshy calyx. Albu- 

 men none. Embryo recurved. — Trees with entire pinnately veined leaves, 

 axillary peduncles, and stoi^t axillary spines. (Named for the early American 

 geologist, William Maclure.) 



1. M. pomifera (Raf.) Schneider. A tree 10-15 m. high; leaves ovate to 

 oblong-lanceolate, poiwted, mostly rounded at base, green and shining ; syncarp 

 EClobose, yellowish-green, 7-10 cm. in diameter. {loxylon Raf. ; Toxylon Sarg. ; 

 M. aurantiaca Nutt.) — Rich soil, s. Mo. to n. Tex. ; extensively used for 

 bedges and sometimes spontaneous eastw. — Wood bright orange. 



7. BROUSSONETIA L'H^r. 



Flowers dioecious ; the sterile in flexuous aments ; calyx 4-parted ; stamens 4 ; 

 filaments inflexed in bud ; fertile flowers in dense globular tomentose heads. 

 Leaves alternate, ovate, often irregularly lobed, pubescent and more or less 

 scabrous. (Named for Auguste Bronssonet, of Montpellier, physician and 

 naturalist.) 



1. B. PAPTRfFERA (L.) Vcnt. (Paper Mulberry.) Often cultivated and 

 said to escape in the Middle Atlantic States and south w. (Introd. from Asia.) 



8. m6RUS [Tourn.] L. Mulberry 



Flowers monoecious or dioecious. Calyx 4-parted ; lobes ovate. Stamens 4 ; 

 filaments elasticaliy expanding. Ovary 2-celled, one of the cells smaller and 

 disappearing ; styles 2, thread-form, stigmatic down the inside. Achene ovate, 



