ORCHIDACEOUS PLANTS. 313 
roots, instead of being ovoid, are palmate or hand-shaped. Both 
kinds of roots are accompanied by the ordinary cylindrical root- 
fibres, covered with hairs, whose principal function is absorption. 
The leaves of the Orchis maculata are sheathed and arranged 
spirally ypon the stem; their lanceolated limbs are generally 
sprinkled with black spots. This study of an orchid, so frequently 
met with, will give a general idea of them. But to realise the 
appearance presented by the plants of this remarkable order, they 
must be seen or imagined as they appear in the tropical forests. Many 
of the tropical orchids are Epiphytes, but not always parasites—that 
1s, they grow in the clefts of branches, and in the angles of roots, 
either erect or gracefully suspended from the branches, but with- 
out drawing their nourishment from them. Their flowers are 
in ears, branches, or tufts, of different sizes, and their - 
colours are often most rich and varied, frequently yielding a sweet 
perfume. They always present an original and somewhat fantastic 
appearance ; now resembling a fly, now a spider, others a butterfly, 
and some a man suspended by the head. The diversity in the 
size and appearance of their flowers, and their strange beauty, 
cause this group of plants to be one of the most cherished orna- 
ments of our hothouses. 
The Arreruuse” are among the least interesting of orchids. 
Dr. Lindley once thought Vanilla of sufficient importance to 
constitute a sub-order, which he has since withdrawn. The 
Vanillaceze are climbing orchids, but not Epiphytes ; the leaves are 
fleshy. , Subcordate at the base, and articulated with the stem, which 
18 Square, and climbs to the height of 20 or 80 feet. The flowers 
are fleshy, the perianthe articulated with the ovarium; the 
Sepals and petals nearly equal, and free at the base, the labellum 
‘8 entire and united with the column; the anthers terminal 
and opercular; the pollen-masses; two, bilobed and granulose. 
, re are eight species, two of them found in Asia and six in 
America. The fruits of most of them are aromatic, and there is 
_ Still some doubt which of these species yield the Vanilla of com- 
_ ‘Mmeree. It is supposed to be the product of several species; 
: Probably the fruit of V. aromatica and V. planifortia, said to 
aS an 80 large a proportion of essential oil and benzoic acid as to 
“Moxicate the labourers who gather it. 
