328 TREES OF NORTH AMERICA 



on the southern keys, Florida; common; often springing up where the ground has been 

 burned over, or otherwise cleared of its forests; on many of the West Indian islands and in 

 Mexico. 



XH. MORACEJE. 



Tree or shrubs, with milky juice, scaly or naked buds, and stalked alternate simple 

 leaves with stipules. Flowers monoecious or dioecious, in ament-like spikes, or in heads on 

 the outside of a receptacle or on the inside of a closed receptacle; calyx of the staminate 

 flower 2-6-lobed or parted; stamens 1-4, inserted on the base of the calyx; calyx of the 

 pistillate flower of 2-6 partly united sepals; ovary 1-2-celled; styles 1 or 2; ovule pendulous. 

 Fruits drupaceous, inclosed in the thickened calyx of the flower and united into a compound 

 fruit (syncarp) . 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 indige- 

 nous in North America, although Broussonetia papyri/era 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 naturalized 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; syncarp oblong and succulent. I. Morus. 



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



2. Madura. 



Flowers on the inside of a closed receptacle; buds naked; syncarp 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, fibrous roots, and winter-buds covered by ovate scales closely 

 imbricated in 2 ranks, increasing in size from without inward, the inner accrescent, mark- 

 ing 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 base, membranaceous or subcoriaceous, 

 deciduous; stipules inclosing their leaf in the bud, lateral, lanceolate, acute, caducous. 

 Flowers monoecious or direcious, 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; staminate hi elongated cylin- 

 dric 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; pistillate sessile, in short-oblong densely flowered 

 spikes; calyx 4-parted, the lobes ovate or obovate, thickened, 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 villose white 

 stigmatic lobes; ovule suspended from the apex of the cell, campy lotropous; micropyle 

 superior. Drupes ovoid or obovoid, crowned with the remnants of the styles, inclosed in 

 the succulent thickened and colored perianth of the flower and more or less united into 

 a more or less juicy compound fruit; flesh subsucculent, thin; walls of the nutlet thin or 

 thick, crustaceous. Seed oblong, pendulous; testa, thin, membranacfeous; hilum minute, 

 apical; embryo incurved in thick fleshy albumen; cotyledons oblong, equal; radicle ascend- 

 ing, incumbent. 



Morus with eight or nine species is confined to eastern temperate North America, the 

 elevated regions of Mexico, Central America and western South America, southern and 



