468 



HENDERSON'S HANDBOOK OF PLANTS 



TWI 



Twin Leaf. The local name of the genus Jeffer- 

 sonia, which see. The plant is also some- 

 times called Rheumatism Root. 



Tydae'a. Derivation not given. Nat. Ord. Ges- 

 neracecB. 



A genus of beautiful herbaceous plants, na- 

 tives of the mountains of New Grenada. 

 There are at present only four described spe- 

 cies, which are better known under their old 

 name of Achimenes, the best known being T. 

 picta. " They are erect, robust herbs, with 

 tine blotched leaves and axillary, bright-col- 

 ored flowers. The calyx is connate with the 

 ovary, the corolla almost funnel-shaped, and 

 five-lobed; the stamens are included, the 

 ovary surrounded by five glands, the stigma 

 five-cleft and the fruit a capsule." The Ges- 

 neracece have been much cut up and divided of 

 late years, so that one hardly knows where to 

 look for the plant he wants to find. See Achi- 

 menes and Gesnera. 



Ty'pha. Cat-Tail Flag. From typhos, a marsh ; 

 referring to the habitat of the species. Nat. 

 Ord. Typhacece. 



T. latifolia, the common Cat-Tail Flag of 

 our marshes, a native of Europe and the East, 

 has become naturalized in almost all parts of 

 the United States. It is also common in Eu- 

 rope. A species with narrow leaves is more 

 rare. The pollen of Typha is inflammable, 

 like that of Lycopodium, and is used as a sub- 

 stitute for it. The "Cat-Tail," in the minds 



ULM 



of most boys, is closely associated with the 

 "Fourth of July," being largely used by them 

 for "setting off" their fire works and ciackers. 

 Typha'ceae. A small natural order of reed-like 

 plants, growing in marshes, ditches, or shal- 

 low water, with long, narrow, parallel-veined 

 leaves, and small flowers densely packed in 

 cylindrical spikes or heads. There are very 

 few species, but some of them are dispersed 

 over nearly all parts of the world. They form 

 two genera, Typha and Sparganium. 



Typho'nium. From Typhon, a mythological 

 giant. Nat. Ord. Aroideoz. 



A genus of tuberous, perennial herbs, differ- 

 ing slightly ootariically from Arum, natives 

 of tropical Asia, the Pacific Islands and Aus- 

 tralia. The species have large, showy leaves, 

 and require the same general treatment as 

 Colocasia. 



Tyto'nia. Water Balsam. Named after Arthur 

 Tyton, by whom many of the oldest inhabi- 

 tants of our gardens were preserved. Nat. 

 Ord. Geraniacece. 



T. natans, the only species, is a stove aqua- 

 tic, its large irregular flowers beautifully 

 variegated with white, red and yellow. It 

 should be grown in rich, loamy soil, in large 

 pots or pans of water, in a warm part of the 

 green-house^ It is a native of tropical Asia, 

 introduced in 1810, and can be increased by 

 seeds sown in spring. Syn. Hydrocera triflora. 



IT. 



TTgni. A genus founded on a single Chilian 

 U species which was at first referred to Eu- 

 genia, but is now generally placed under 

 Myrtus. M. Ugni has very agreeably flavored 

 aromatic fruit, and succeeds admirably in the 

 Southern States. See Myrtus. 



U'hdea. U. bipinnatifida is a stout-habited 

 Mexican composite plant, valuable for sum- 

 m-r decoration. It is of robust growth, attain- 

 ing a height of from four to six feet in deep, 

 rich soils. The branching stems are clothed 

 with slightly silvery or glaucous, irregular and 

 deeply cut foliage. In sheltered positions on 

 the lawn it forms noble, isolated specimens, 

 or it may be judiciously grouped along with 

 dark-leaved Ricinus or Cannas. U. pyrami- 

 data is of a lighter and fresher green than 

 the preceding, and is larger in habit, having 

 more of the aspect of Malva in foliage. They 

 are both readily propagated from cuttings, 

 which are freely produced by old specimens 

 taken up carefully in autumn and re-potted. 



U'lex. Furze. Gorse or Whin. Said to be 

 taken from the Celtic ac, a point ; in allusion 

 to its prickly branches. Nat. Ord. Legumi- 

 nosoB. 



A genus of very beautiful, evergreen shrubs, 

 with yellow flowers, both double and single, 

 indigenous to Great Britain and the south of 

 Europe. They are highly esteemed for hedge 

 plants, and the young tops are cut and fed to 

 cattle and horses ; but their value as a food 



plant is considerably questioned. None of the 

 species thrives in this country, being too 

 tender for our Northern States, and too 

 impatient of our tropical summers in the 

 South. 



Uliginose. Inhabiting swampy places. 



U'Uucus. From Ulluco, the Quitan name. 

 Nat. Ord. Chenopodiacece. 



U. tuberosa, the only species, is a half- 

 hardy, fleshy, decumbent herb, with a stem 

 throwing out thread-like branches, which, 

 when they enter the earth, produce edible 

 tubers. The plant is extensively cultivated for 

 these tubers in the mountains of Bolivia and 

 Peru, under the name of Oca-quina. It is in- 

 teresting, as having been unsuccessfully tried 

 as a substitute for the Potato. Syn. Mclloca. 



TTlma'ceee. Now included as a sub-tribe of Urti- 

 cacecB. 



U'lmus. Elm. Supposed to be from the Saxon 

 word elm or ulm, a name which is applied, 

 with very slight alterations, to the trees of 

 this genus in all dialects of the Celtic tongue. 

 Nat. Ord. Urticacece. 



This genus takes the first rank in the great 

 army of American trees. When asked, "What 

 is the handsomest tree in America ? " we un- 

 hesitatingly say, " U. Americana, the Ameri- 

 can Water or White Elm. " Of the several 

 species that make up this genus, none in any 

 respect compares with this. U. fulva is the 

 common Red or Slippery Elm. U. racemosa 



