46 Rhodora [Marcu 
yield, a million seeds per capsule in some cases, does not indicate a 
low degree of specialization in a group that depends for successful 
germination on a symbiotic fungus. For every dozen seeds that fall 
where endotrophic fungi of the proper type are present, millions must 
drift to sterile ground and suffer extinction. Consequently in over- 
coming any economic disadvantages that high yield of seeds implies 
the orchids through adaptation of seed yield to the exigencies of a 
symbiotic union have manifested a high degree of success, as success is 
measured in the human interpretation of organic development. This 
line of reasoning implies, quite naturally, that orchi” fungus symbio- 
sis is a good thing, that it has been advantageous and admirable. 
It denies that an association such as orchid-fungus symbiosis is indi- 
cative of degeneracy having resulted on the part of the orchid with a 
consequent moribund constitution. Sparse distribution, notwith- 
standing an extravagant production of seed, seems to be an indisput- 
able piece of evidence from which to argue that orchids are in a precar- 
ious biological situation, but sparse distribution need not be taken as 
an indication of impending extinction through an unfortunate luxury- 
symbiosis, if we admit that the orchids are perfectly adapted to sparse 
distribution, even though incapable of taking possession of the earth. 
Harvarp University, BUSSEY INSTITUTION. 
PLATE 135. 
GooDYERA PUBESCENS D. Br. 
Plant, approximately natural size with flowering and fruiting racemes, 
detached. 
Fig. 1. Flower much enlarged to show the perianth. 
Fig. 2. Flower sectioned to show relation of the labellum and gynostemium 
to the ovary, sepals and petals. i 
Fig. 3. Gynostemium drawn to show position of stigma and anther. 
Fig. 4. Pollinia. 
Fig. 5. A pollen tetrad. 
Fig. 6. The mature seed 
Drawings by Blanche Ames. 
PLATE 136. 
GooDYERA PUBESCENS D. Br. 
Fig. 1. Protocorm (X25), showing testa still adherent to the base; spreading 
hair-like structures through which the hyphae pass to and from 
the humus, and the growing tip. The darker portion indicates the 
extent of distribution of the fungus. 
Fig. 2. Four stages in the development of young plants (x2). 
Fig. 3. The upper portion of a hair-like process through the tip of which two 
fungal hyphae have passed. 
Fig. 4. Part of a hair-like process in which fruit-like structures have formed. 
Fig. 5. A cell from the lower part of the protocorm showing a large nucleus 
closely appressed to a mass of digested hyphae. 
Fig. 6. An earlier stage of digestion than that shown in fig. 5. The nueleus 
and partly digested fungus are surrounded by a skein of hyphae. 
Figs. 1-3 from drawings by Blanche Ames. Figs. 4-6 from drawings by 
the author. 
