2 14 ORCHIDE^ 



5. Bird's-nest or Tway-blade {Listera). 



1. Common Tway-blade {L. ordfa). — Stem downy above, with only 

 two opposite large egg-shaped leaves ; column of fructification with a crest 

 which includes the anther. This plant, well named Tway-hlade, is readily 

 distinguished from all our native orchids l)y the two broad, glossy, green, 

 strongly -nerved leaves, often eight inches long. The plant is from a foot to 

 a foot and a half high, the flowers small in proportion to leaf and stem, of a 

 yellowish-green hue, and forming a long loose spike from April to June. It 

 is found in shady places, in orchards and pastures, and still more commonly 

 in woods. Its rootstock is composed of numerous long fleshy fibres, connected 

 in bundles by a main fibre. The two-lobed lip is slightly hollowed at its 

 base, from which a channel runs down the centre in which honey is secreted. 

 Flies and beetles follow this up to the end, where their heads come in con- 

 tact with the tongue-shaped portion (rosfdlum) of the column on which the 

 pollinia stand. At the touch the rostellum exudes a drop of liquid cement 

 at the base of the pollinia, which therefore become attached to the insect's 

 head, and are carried off to fertilize other Tway-blade flowers. 



2. Heart-leaved Tway-blade (L. corddta). — Stem smooth, with two 

 opposite heart-shaped leaves ; column without a crest ; lip with a tooth on 

 each side at its base. This is a much smaller species than the last, its stem 

 rarely exceeding six inches in height, and its smooth leaves being usually 

 little more than an inch long. It produces a few dull brownish-green flowers, 

 very small, and forming a loose spike ; these expand from June to August, 

 and have somewhat spreading sepals and a narrow drooping lip ; the root- 

 stock consists of a few stout filjres. It occurs in mountainous districts and 

 on turfy moors, with a marked fondness for heather as a protection. It is 

 rare in Ireland. 



3. Commion Bird's-nest {L. nldus-dvis). — Stem leafless, but beset with 

 sheathing brown scales ; column without any crest ; lip linear-oblong, with 

 two spreading lobes. This is a very singular plant — stem, scales, and 

 flowers all being of a dingy brown hue ; so that its first appearance is that 

 of a withered stem, till on examination we observe its succulent nature. Its 

 somlwe aspect and leafless condition, so like that of some of our native 

 parasitic plants, as well as its growth among the fallen leaves around the 

 trunks of trees, led to the opinion that this Orchid was parasitical in habit. 

 Mr. Bowman, Avho examined the plant with much care, says : "It has long 

 been doubted whether it is strictly parasitical. Whatever it may be in the 

 earlier stages of its growth, it certainly is not so in its more advanced state. 

 If it be carefully got up in a clod, and the soil afterwards washed from 

 around it, the leaves (that is, the scaly appendages) of the central rootstock, 

 or caudex, may be seen to terminate in a short curved spur, which tapers to 

 a fine point, and evidently is not attached to any other vegetable. The 

 cuticle of the stem and its bracts have no perspiring pores." It is really a 

 saprophyte, like coral-root, feeding upon decaying leaves. 



This plant received its old name of Bird's-nest from the short, thick, fleshy 

 entangling fibres of its roots, which might remind us of the sticks used by 

 some of our larger birds in the framework of their nests. The young plants 



