^ PLEUEOTHALLIS. 



introduced into British gardens^ bnt very few indeed hare remained 

 long in cultivation^* and scarcely a dozen liave been considered worthy of 

 being figured in works other than those purely devoted to science. The 

 flowers of most of the known species are small, inconspicuous and 

 without fragrance, but there are many of singular form and gem- 

 like beauty which, requiring but little space for their cultivation, should 

 induce amateurs to give some attention to them. The species de- 

 scribed below are among the best known ; the cultural treatment of 

 these, as will be readily inferred from their alpine character, is that 

 of cool orchids such as we have given in detail under Masdevallia 

 and Odontoglossum. 



To assist the reader to distinguish the species of Pleurothallis 

 from those of the closely allied genera, we subjoin a diagnosis of 

 the chief characteristics of the flower : — 



The dorsal sepal is free ; the lateral two are always coherent into 

 one that is bifid or bipartite at the apex ; the petals are shorter and 

 narrower than the sepals ; the lip, which is generally shorter than the 

 petals, is articulated at the base of the column. The column is of 

 the same length as the lip, or a little shorter ; the pollinia are tAvo 

 in number, and are either pear-shaped or of sub-globose form. 



In their vegetation the species of Pleurothallis are dwarf, often 

 minute plants. — 



The stems are simple, rarely exceeding a few inches in height 

 enclosed in sheathing scales, and terminating in a solitary leaf that 

 varies in size and form in the different species. The inflorescence 

 springs from the base of the leaf and is generally racemose, but some- 

 times a 1 — 2 or few-flowered peduncle. 



Pleurothallis is derived from TrXivpov (pleuron), "a rib" or side, 

 and OuWd) (thallo), '"^ to bloom," probably in allusion to the 

 bilateral position of the floral segments with respect to the axis. 



Pleurothallis Barberiana. 



A minute stemless plant. Leaves petiolate, elliptic, Iialf-an-inch long. 

 Peduncles cai)illary (as slender as a hair), 2 — 4 inches long, drooping, 

 6 — 12 flowered. Flowers small; sepals free, oblong-lanceolate, aristate, 

 whitish spotted with deep purple ; petals ovate, apiculate, longer than 

 the column, whitish with paler spots than the sepals ; lip " a linear- 

 oblong, terete, sub-clavate, solid body of purple colour blotched with 



* See Hemsley's enumeration in the Gardeners'' Chronicle, XV. (1881). p. 784 ; XVI. pp. 10 

 and 42. 



