IIaxiu'.ook of Trf.f.s of tjif Noktiifkm Statfs axu Canada. 4:^3 



of tlic iiiipf'T' Iciivcs; calyx dcoply .l-T-lohod. (IcciiliKius ; staiiicns iiiciii'vi'd in llic Imd and in 

 the staminate flowers erect and exserted, those of the perfect flowers remaining short, 

 ovary sessile, ovoid and crowned by two diverging reflexed styles, stigmatic on the inner faces ; 

 ovule anatropous. Fruit a sub-globose drupe, with firm skin, thin sweetish flesh and bony 

 or rugose pit ; seed with curved embryo and scanty albumen. 



KKV TU THE SPECIES. 



Leaves sharjily aii<l coarsely serrate C. occidentalis. 



Leaves enlire'or nearly so". C Mississippiensis. 



I'ur species sec i>i>. liU-lUo. 



MULBERRY FAMILY. MORACE^. 



Trees, shrubs aiul herbs of over nine liundied species, generally willi milky juice and 



natives of temperate and tropical regions. Tlicy are grouped in fifty-four genera of which 



four are represented in Xoi'th American trees, three being indigenous and the fourth a 



naturalized species. 



Leaves conduplicate or involute in the bud. petiolate. alternate, deciduous, with caducous 

 stipules inclosing the leaf in the bud. Floirrrs monoecious or diwcious. small, in ament-like 

 spikes or heads, from the axils of caducous bud-scales or of the lower leaves of the shoots 

 of the season; calyx 3-5-lobed or parted; corolla none; stamens 1 to 4. inserted on the 

 bases of the calyx-lobes; ovary superior, 1-2-celled ; styles 1-2; ovules solitary, anatropous 

 and pendulous. Fruit an aggregation of drupelets, each inclosed in the thitk fleshy calyx. 



KEY TO THE ({EX ERA. 



Both staminate and pistillate flowers in spikes: leaves dentate and lobcd : compound fruit 



oblong Morus. 



Staminate flowers racemose; pistillate capitate 



Leaves crerwite-serrate, velvety and on vigorous shoots, lobed Broussonetia. 



Leaves entire, glabrous, not lobed Toxylon, 



THE MULBERRIES. Genus AIORUS L. 



Trees of eight or ten species, with milky juice and mostly of the lroi)ical and noi-th 

 temperate regions of both hemispheres. Two are indigenous to the United States, one being 

 found along the Mexican frontier and the other in most of the Atlantic states. A third 

 is a species introduced from .Japan and eastern Asia and extensively naturalized in easteiu 

 T'nited Srates. 



Leaves serrate-dentate and sometimes 3-5-lobed or mitten-shaped, all forms often on 

 the same tree. 3-nerved at bas-e. Flowers small, appearing with the unfolding of the leaves 

 ')v soon after; the staminate in cylindrical, pedunculate ament-like spikes; calyx deej ly 

 i-lobed ; stamens 4, opposite the cn.lyx lobes, inflexed in the bud, straightening out elastically 

 ( thereby scattering the pollen ) and becoming exserted ; anthers 2-celled, introrse, longitud- 

 inally dehiscent ; pistillate flowers sessile, in shorter compact spikes ; calyx 4-parted. with 

 thick persistent lobes enveloi)ing the flattened ovoid ovary which is crowned with two white 

 spi'eading stigmas. Fruit a blackberry-like aggregation of drupelets { sinrarii). each tijiped 

 U'ith the remnants of the styles and formed by the nutlet enveloped by the succulent enlarged 

 and colored calyx ; seed pendulous with curved embryo and scanty albumen. 



Morus is the ancient Latin name of the Mullx rriz-tne. 



KEY TO THE SPECTES. 



Leaves rough abo\'e, pubescent beneath ; fruit purjilc M, rubra. 



Leaves glabrous or nearly so both sides ; fruit usually white M. alba. 



For species see jip. HXl'-tHH. 



THE PAPER MULBERRY. Gi-xus r.ROUSSOXETIA \'i:xt. 



Trees and shrub-; of three or four species with milky juice and natives of eastern Asia, 

 >ne si)ecies beir.g widt ly naturaliz-d in eastern riiited Stales. 



Leaves both alternate and ojjposite. (Mitire or toothed, serrate, witlioiit lo')(>s or variously 

 1-5-lobed, petioled. 3-nerved at base. Floinrs dMccious. stamin;ile in cylimli-ical nodding 

 ament-like spikes; calvx 4-i)art(>d ; stamens 4; pislillale ll.iwers capitate wiiji tubular iierianth. 

 stalked ovary ami 2-cleft style. Fruit in a glnbulai- head and nutlet exserted with enlarged 

 red lleshv stipe and i)erianth. 



Named in honor of 7'. .V. V. lirt.ussonct. a French naturalist. 



For sj,e(i<s see pp. Jllll ..'01. 



28 



