XXXVIII.— THE MARSH HELLEBORINE. 
Epipactis longifolia Allion i. 
A N EVER-ENDING subject for wonder in the study of plant-structure and 
plant-life is the manifold possibilities in the variants upon one type, whether 
in anatomy or in physiology. In no group is this variety in unity more remarkable 
than it is among Orchids. The many terrestrial representatives of the Family are all 
perennial and herbaceous and have more or less of a rhizome giving off fibrous roots, 
though in many cases, as we have seen, some of these roots are modified as food- 
reservoirs into tubercles. Their aerial stems are generally somewhat succulent or 
soft and juicy, with a glabrous and often polished surface ; and their leaves are simple 
in outline, sheathing at the base, distinctly parallel- veined, and also generally glabrous 
and polished. The inflorescence is in all cases racemose ; and (with the exception of 
the genus Cypripedium , the Ladies’-slipper Orchids) the flowers are constructed on a 
very uniform plan and are generally inverted by the twisting of the inferior ovary or 
the pedicel. Modified from the typically Monocotyledonous arrangement of fifteen 
floral leaves in five alternating whorls of three each, we find generally a petaloid 
perianth of three outer and often sub-equal leaves or sepals and three inner ones more 
distinctly bi-lateral in their symmetry to the median plane, the petal which is strictly 
posterior but from the inversion or resupination appears anterior, being a large landing- 
place for insect-visitors or labellum. By careful anatomical analysis traces of two 
stamens of the outer whorl may be detected as incorporated in this labellum, while 
the one fertile or pollen-bearing anther is the anterior one of this whorl, and very 
little trace remains of the inner whorl of three. Orchids can be recognised at a 
glance by the union of their essential organs into a central column , which earned for 
them Linne’s descriptive term gynandrous (from the Greek yvuirj, gune , a woman ; 
ai’&pos, andros, of a man). In this structure the inferior, one-chambered, many-ovuled 
ovary is surmounted, with little or no style, by a tri-lobed stigma, two lobes of which 
become receptive, while the median one is modified into a peculiar structure known 
as the rostellum ; while the one pollen-bearing anther — the anterior one of the outer 
row — rises above this stigma, with no distinct filament. In most cases the pollen in 
each of the two chambers of this anther is united into a club-shaped mass or 
pollinium , the individual pollen-grains being tied together by elastic thread-like 
extensions of their coats into little packets or massuhe , the united threads from which 
unite into the stalk, known as the caulicle or caudicle , of the entire pollinium, which 
ends in a viscid body known as the retinaculum , attached more or less to the rostellum. 
On this general plan we have a marvellous number of variations. Not only 
does the perianth vary in the size, colour, and markings of its leaves, but the form 
of the labellum more particularly seems almost infinitely varied. In the Tribe 
Neottinirf, to which the Lady’s Tresses, Tway-blade, Bird’s-nest and Helleborine 
Orchids belong, there are more often numerous fleshy root-fibres than two tubercles ; 
