150 



HENDERSON'S HANDBOOK OF PLANTS 



EXO 



the name of the genus. It is a smooth shrub 

 or dwarf tree, with alternate nearly lance- 

 shaped entire leaves, the stems terminated 

 by racemes of handsome white flowers, which 

 appear in May and June, and are about an 

 inch in diameter. They have a bell-shaped 

 calyx with a five-parted border, five rounded 

 petals, and fifteen to twenty stamens. The 

 plant is also known as SpircBa grandiflora. It 

 is a beautiful tall-growing slirub, worthy of a 

 place on the lawn and in the shrubberj'. It is 

 still a rare plant in the United States, chiefly 

 because it is dilficult to propagate, and in 

 consequence is not easy to get. It is propa- 

 gated by seeds, layers, or suckers. 



Exogens. A name given to one of the great 

 classes of the vegetable kingdom, correspond- 

 ing with the Dicotyledons. The name Exogen 

 is from the Greek, and signifies aiitivard and 

 to grow, meaning growing outwardly, and has 

 reference to the manner in which the Avoody 

 circles are produced, viz., from the center 

 outwardly toward the circumference. The 

 age of an exogenous tree, especially in tem- 

 perate climates, may be determined by count- 

 ing the number of zones or circles in the 

 woody stem, each circle marking one year's 

 growth, and the last formed circle being ex- 

 ternal. The characters of the class are given 

 under Dicotyledons, which see. 



Exogo'nium. From exo, external ; referring to 

 the exserted stamens. Nat. Ord. Convolvula- 

 cecB. 



The few species that are included in tliis 

 genus are closely allied to, and very nearly 

 resemble the tuberous-rooted IpomcRos. They 

 are desirable climbers, flowering freely nearly 



FAG 



the whole summer. During winter the tubers 

 should be kept dry and free from frost. E. 

 purga, a Mexican species, has beautiful sal- 

 ver-shaped, purplish flowers, and furnishes 

 the true Jalap tubers of commerce. These 

 are roundish, of variable size, the largest being 

 about as large as an orange, and of a dark 

 color. They owe their well-known purgative 

 properties to their resinou.9 ingredients. They 

 can be rapidly increased by cuttings, or by 

 division of tubers in spring, like the Dahlia. 



Exosmose. That force which causes a viscid 

 fluid lying on the outside of an organic mem- 

 brane to attract watery fluid through it. 



Exoste'mma. From exo, external, and stemma, 

 a crown ; referring to the exserted stamens. 

 Nat. Ord. Rubiacem. 



A genus of tropical trees or shrubs, valued 

 more for the medicinal properties they pos- 

 sess, than for the beauty of their foliage or 

 flowers. They are natives of the West Indies. 

 One of the species, E. Caribmum, has become 

 naturalized in southern Florida. The bark 

 possesses the same actiye principle as that of 

 the Cinchona. 



Exotic. Plants that are brought from foreign 

 countries. Not native. 



Exserted. Where one part protrudes beyond 

 another by which it is surrounded ; as the 

 stamens or stjdes beyond the mouth of some 

 tubular corollas. 



Eye. A term in gardening for a leaf-bud ; also 

 for the center or the central markings of a 

 flower. 



Eye-bright. See Euphrasia. 



F. 



Fa'ba. The old Latin name for the Bean, 

 noAV included under Vicia, which see. 



Fabaceae. A sub-order of LeguminoscB. 



Fabia'na. Named after F. Fabiano, a Spaniard. 

 Nat. Ord. Solanacem. 



A small genus of half-hardy evergreen, 

 heath-like shrubs. F. imbricata, the best 

 known species, is a neat evergreen shrub of 

 compact habit, densely covered, during the 

 spring months, with pure white tubular 

 flowers. Propagated by seeds or from cuttings. 



Fadye'nia. Named after Dr. Fadyen, author of 

 a Flora of Jamaica. Nat. Ord. Polypodiacece. 



F. prolifera, the only species, is a curious 

 Fern, a native of the West Indies. It grows 

 but a few inches in height ; the fronds have 

 netted veins, and are remarbable for the large 

 size of the sori. It was introduced from 

 Jamaica in 1843, and is occasionally found in 

 choice collections. Propagated by spores. 



Faecula. The farinaceous matter which forms 

 starch, etc. 



Fage'Ua. Named after Fagel, a botanist. Nat. 

 Ord. LeguminoHcp.. 



A genus of green-house evergreen, twining, 

 herbaceous plants, found in South Africa and 

 Abyssinia. The leaves somewhat resemble 



those of Phaseoltis, but are smaller. Their 

 flowers are pea-shaped, yellow, and borne on 

 long axillary racemes. Young plants are ob- 

 tained from seeds. 



Fagopy'rum. Buckwheat. From phago, to 

 eat, and pyro8, wheat ; seeds edible. Nat. Ord. 

 PolygonacecB. 



F. esculentum, the only species worthy of 

 notice, is our common buckwheat, which see. 



Fa'gus. The Beech. From phago, to eat ; in 

 early ages the nuts of the Beech-tree were 

 used as food. Nat. Ord. Cupuliferm. 



A small genus of hardy deciduous trees, re- 

 markable for their graceful and symmetrical 

 habit of growth, and their great size and 

 beauty, which render them objects of admira- 

 tion, whether in their native woods, or when 

 planted on the lawn for shade. F. ferruginea, 

 the American Beech, is one of the tallest and 

 most majestic of our forest trees. It grows 

 most abundantly in the Middle and Western 

 States,though common east of the Alleghanies, 

 attaining its greatest size on the banks of the 

 Ohio, where the trees are frequently found 

 100 feet high, with a diameter from three to 

 four feet ; its foliage is superb, and its general 

 appearance magnificent. The sexes are borne 

 on different branches of the same tree. The 



