THE TAMU8 FAMILY. 467 



CXLIX.— THE TAMUS FAMILY. Dioscoredce(B. 



A small family of climbing plants, occupying an intermediate posi- 

 tion between Exogens and Endogens, and with the exception of the 

 common English Tamils, altogether tropical. The yam, or Dioscorea 

 sativa, is the only important species. The roots are very large and 

 tuberous ; the leaves broad and net-veined, with distinct petioles, 

 which are often articulated to the stem ; the flowers small, trimerous, 

 and unisexual. The only exotic species known to Manchester botany 

 is the extraordinary hot-house plant called the " Elephant's-foot," or 

 Testudindria elephuntipes. 



The Tamus has a large fleshy rootstock, which is white within, but 

 externally black. From this there spring'up, every year, in April and 

 May, round, slender, and leafy stems, that twine among bushes and 

 small trees to the length of six or eight feet or more, and often hang 

 among them in graceful festoons, several stems twining and wreathing 

 together, as in the honeysuckle. The leaves are alternate, of an elegant 

 narrow heart-shape, two to four inches long, very pointed, petiolate, 

 quite entire, glabrous, and of a bright and shining green. The 

 flowers are small, regular, deeply six- cleft, greenish- white or yellow, 

 and borne in very elegant, light, lax, axillary racemes, the males and 

 females being on separate plants. The racemes of male flowers are 

 generally longer than the leaves, and those of the females rather 

 shorter. By autumn they are transformed into copious clusters of 

 brilliant scarlet and viscid berries the size of a pea, and exceedingly 

 conspicuous and ornamental among the frist-fading foliage, their own 

 being of a fine yellow. The stems die with the winter. Stamens six ; 

 ovary inferior ; styles or stigmas three. 



HABITATS AND LOCALITIES. 

 Tamxts — [Tamus communis.) 

 Woods, thickets, doughs and shady hedges ; rather rare. Cotterill, 

 and in all the woods thereabouts, plentiful. The same at Thelwall, 

 below Lymm, in the lanes near the powder-mills. Woods in the 

 Reddish Valley. Plentiful near the new church, Culcheth, near 

 Warrington. Crookley Wood, near Stockport, but now nearly 

 destroyed by the herbalists. A root was once got in Crookley Wood, 

 weighing 28 lbs. (Mr. Isaac Williamson.) FI. June, July. Berries in 

 September and October. 



E. B. ii. 91 ; Baxter, iv. 291. 



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