38 Rhodora [Marcu 
demonstrate that nonsymbiotic germination is possible if by artificial 
means seeds are supplied with essential food materials in an available 
form. | 
Under natural conditions orchids behave in a manner that seems 
to indicate that the dependence on symbiosis, of a kind, is prevalent. 
Even under the artificial conditions, that characterize horticultural 
enterprises, there are indications that symbiosis is essential for success- 
ful germination, unless methods such as Knudson described are adopt- 
ed. 
Many years have passed since my interests were centred in the rais- 
ing of orchid species and hybrids, but it is clear in my memory that 
seeds sown at the base of a luxuriant orchid plant on a substratum 
that had become thoroughly settled, gave better promise of germin- 
ation than those sown on sterilized media in special pots or baskets 
that had been skilfully prepared and kept under exceptionally clean 
conditions. And my memory is clear on still another point, that a 
neighbor who had enjoyed successful horticulture in greenhouses that 
would have offended, through their rich growth of thallophytes, the 
carefully trained gardener of a model establishment, raised orchids 
from seed with uncanny success and inexplicable regularity. When 
I first read the classic paper which linked Noél Bernard’s name indi- 
solubly with symbiosis in the orchids, I imagined that I had at last 
found a very plausible explanation of the results which I had observed 
at home and had studied abroad in the realm of orchids raised from 
seed. 
Under natural conditions I have observed that germinating orchids 
are normally associated with the characteristic fungi of endotrophic 
mycorrhiza. In fact, as a result of my observations, I have been led 
to believe that mycorrhiza are not only influential in germination 
under natural conditions, but that they may have a great deal to do 
with the manner in which orchids arrange themselves on the ground or 
on trees and may account for peculiarities of distribution that are 
well known to collectors in tropical countries and to those systemat- 
ists who work among orchids. As my observations stimulated inter- 
esting conclusions I decided to seek for evidence that would either 
sustain or demolish my theories. 
