302 TREES OF NORTH AMERICA 



Grande, and westward through New Mexico and Arizona to southern Utah and 

 Nevada, and the western rim of the Colorado Desert in California; and in Lower 

 California; in eastern Texas usually on dry limestone hills; westward only near the 

 banks of streams in mountain canons. 



I 



XII. MORACE-S3. 



Trees or shrubs, with milky juice, scaly or naked buds, and stalked alter- 

 nate simple leaves with stipules. Flowers monoecious or dioecious, in ament- 

 like spikes or heads on the outside of a receptacle or on the inside of a closed 

 receptacle ; calyx of the staminate flower 3 or 4-lobed or parted ; stamens 1-4 

 inserted on the base of the calyx ; calyx of the pistillate flower of 3-5 partly 

 united sepals ; ovary 1-2 celled ; styles 1 or 2 ; ovule pendulous. Fruits dru- 

 paceous, inclosed in the thickened calyx of the flower and united into a com- 

 pound fruit. The Mulberry family is widely distributed with fifty-four genera 

 confined largely to the warmer parts of the world. Three genera only, all 

 arborescent, are indigenous in North America, although Broussonetia papyri- 

 fera, Vent., the Paper Mulberry, a tree related to the Mulberry and a native 

 of eastern Asia, and the Hop and the Hemp are more or less generally natural- 

 ized in the eastern and southern states. 



CONSPECTUS OF THE NORTH AMERICAN GENERA. 



Flowers on the outside of the receptacle ; buds scaly. 



Flowers in ament-like spikes; compound fruit oblong and succulent. 1. Morus. 



Staminate flowers racemose, the pistillate capitate ; compound fruit dry and globose. 



2. Toxylon. 



Flowers on the inside of a closed receptacle ; buds naked ; compound fruit subglobose to 

 ovoid, succulent. 3. Ficus. 



1. MORUS, L. Mulberry. 



Trees or shrubs, with slender terete unarmed branches prolonged by one of the 

 upper axillary buds, scaly bark, and fibrous roots. Winter-buds covered by ovate 

 scales closely imbricated in 2 ranks, increasing in size from without inward, the 

 inner accrescent, marking in falling the base of the branch with ring-like scars. 

 Leaves conduplicate in the bud, alternate, serrate, entire or 3-lobed, 3-5-nerved at 

 the base, membranaceous or subcoriaceous, deciduous; stipules inclosing their leaf 

 in the bud, lateral, lanceolate, acute, caducous. Flowers monoecious or dioecious, 

 the staminate and pistillate on different branches of the same plant or on different 

 plants, minute, vernal, in pedunculate clusters from the axils of caducous bud-scales 

 or of the lower leaves of the year, the staminate in elongated cylindrical spikes; 

 calyx deeply divided into 4 equal rounded lobes; stamens 4, inserted opposite the 

 lobes of the calyx under the minute rudimentary ovary; filaments filiform, incurved 

 in the bud, straightening elastically and becoming exserted; anthers attached on 

 the back below the middle, introrse, 2-celled, the cells reniform, attached laterally to 

 the orbicular connective, opening longitudinally; the pistillate sessile, in short- 

 oblong densely flowered spikes; calyx 4-parted, the lobes ovate or obovate, thick- 

 ened, often unequal, the 2 outer broader than the others, persistent; ovary ovoid 

 flat, sessile, included in the calyx, crowned by a central style divided nearly to the 

 base into 2 equal spreading filiform villous white stigmatic lobes; ovule suspended 

 from the apex of the cell, campylotropous; micropyle superior. Drupes ovate or 



