262 THE ORCHID REVIEW. {[SEPTEMBER, 1912. 
‘higher phase of development in the great subdivision Vandez, in which the 
culminating point of development of the Orchidacez is reached. The 
essential character of the Vandez lies in the character of the rostellum 
and pollinary apparatus. Here the rostellum has more than a secretory 
function, for it supplies also a stipes which serves to connect the viscid 
‘gland with the pollinia, and the line of separation of the stipes from the rest 
of the rostellum is by a zone of hyaline tissue, ultimately forming a line of 
disarticulation similar to that by which a leaf is thrown off at its fall in 
autumn. The stipes of the Vandez must not be confused with the 
caudicles of other groups, for it is a part of the female whorl of the flower, 
while the caudicles belong to the male whorl, and are, in fact, pollinary 
appendages formed of modified pollen grains. The union between the stipes 
of the rostellum and the pollinia takes place about the time that the flower 
reaches maturity and prepares to open. Calanthe and some other genera 
of Epidendrez were referred to Vandez before this distinction was properly 
understood, while Ione and a few others have since been transferred there 
because of a stipes-like appendage to the pollinia. But this view of the 
origin of the stipes in Ione requires confirmation, for in other respects the 
genus is so close to Bulbophyllum as to have been actually referred to it. 
It is also nearly allied to Acrochzne and Monomeria, which, with a few 
others, have been regarded as in a transition state between the two tribes, 
though the so-called stipes is apparently caudicular in origin. 
The genera of Vande have already been briefly outlined, and we need 
only recall the highly complex nature of the flowers in some of the higher 
genera, as in Stanhopea and Coryanthes, the remarkable structure and 
mode of fertilisation having been fully described (O.R., xviii. p. 323); in the 
remarkable genera Catasetum and Cycnoches, in some of which the sexes 
are so diverse as to have been referred to different genera ; in the various 
genera of Oncidiew, some of which are highly specialised, and of which we 
may mention Comparettia, in which the lateral sepals are extended into a 
long spur, which includes two spur-like horns produced from the lip, the 
still more complex Cryptocentrum ; and, lastly, in some. of the genera of 
Sarcanthee, which show various complexities, as the double spur of 
Diplocentrum, the divided pollinary appendages of Mystacidium, and the 
diversely-coloured flowers of Arachnanthe Lowii, the cause of which remains 
a mystery. 
In vegetative characters the Vande exhibit a further advance in 
complexity. The terrestrial genera are now in a great minority, and there 
is a great increase in number of true epiphytes—those that grow directly 
upon the bark of trees, rather than upon accumulations of vegetative matter 
among the branches, and push out long aérial roots, which serve the double 
purpose of securing a firm hold for the plant and of absorbing liquid food 
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