WARM ORCHIDS. 107 
would add “ of course ”—a striking difference. In 
the geographical distinctions of species will be 
found the key to whole volumes of mystery that 
perplex usnow. I once saw three Odontoglossums 
ranged side by side, which even an expert would 
pronounce mere varieties of the same plant if he 
were not familiar with them—Od. Williamsz, Od. 
grande, and Od. Schlieperianum. The middle one 
everybody knows, by sight at least, a big, stark, 
spread-eagle flower, gamboge yellow mottled with 
red-brown, vastly effective in the mass, but indivi- 
dually vulgar. On one side was Od. Williamsz, 
essentially the same in flower and bulb and growth, 
but smaller; opposite stood Od. Schlieperianum, 
only to be distinguished as smaller still. But 
both these latter rank as species. They are 
separated from the common type, O. grande, by 
nearly ten degrees of latitude and ten degrees of 
longitude, nor—we might almost make an affidavit 
—do any intermediate forms exist in the space 
between; and those degrees are sub-tropical, by 
so much more significant than an equal distance in 
our zone. Instances of the same class and more 
surprising are found in many genera of orchid. 
The Frontino verzllartum grows “ cooler,” has a 
much larger bloom, varies in hue from purest 
white to deepest red, and flowers in May or June. 
