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HARVEY E. STORK 
micrograph (fig. lo), the black dots representing basidia. As the sterig- 
mata grow from the four cells of a basidium, the cells split apart to some 
extent downward. The globose basidia measure 15 ;u in diameter when 
mature, and the sterigmata are slender like the hyphae of the plant and 
attain a length (up to 30 /jl) that gives them the general appearance of germ 
tubes rather than of sterigmata. It was suggested that the Tremella be 
described as a new species, but the characteristics that are really distinguish- 
ing are so few in this group that it is perhaps better not to multiply species 
until the group is better understood. 
Several efforts were made to infect the fruit bodies of Aleurodiscus 
Oakesii with the Tremella by introducing the mycelium and the conidia on 
the young fruit bodies. The Tremella never showed any active growth 
when thus transferred. 
After the Tremella has had opportunity to grow for some time upon 
the fruit bodies of the host, these latter are often so completely incrusted 
that one fails to recognize their identity, and the twig appears to be covered 
merely with a group of little pulvinate plants of the Tremella, Two such 
fruit bodies are shown in cross section (figs. 10, 11). This leads us to recall 
other cases of Tremellas associated with different fungi. In 1894 Dangeard 
(5) described and figured the association of the mycelia of Dacryomyces 
deliquescens and Tremella sp., the two finally forming a common hymenium. 
He speaks of this as a case of symbiosis. Fries (8) described the species 
Tremella hiparasitica growing on the stipe of Nyctalis parasitica, and 
Tremella parasitica, reported by Schweinitz as growing commonly on Cla- 
varia gigantea Schw. in North Carolina. Of this, he uses the significant 
phrase, "non a Clavaria separabilis." 
It is easy to think of the plants commonly placed in the genus 
Tremellodendron as members of the Thelephoraceae that have Tremellas 
intimately associated with them. The characters of the hymenium most 
closely resemble those of the hymenium of Sebacina TuL, which is a genus 
with decidedly incrusting tendencies. Other genera in this class are Proto- 
hydnum and Protomerulius of A. Moller. 
However, regardless of what our surmises may be concerning the com- 
posite nature of the plants of these genera, we can arrive at definite proof 
only by producing them through "synthesis" in cultures. In this connec- 
tion I quote from a personal letter of Professor R. A. Harper: 
"There are a number of forms which have been listed under various 
other genera which are, in my opinion, incrusting if not parasitic members 
of the Tremellineae. I have always had a suspicion that the Tremello- 
dendron question is mixed up with something of this sort." 
Development and Morphology of the Fruit Body 
Pure cultures of the mycelium of both Aleurodiscus amorphus and A. 
Oakesii have been obtained by suspending the fruit bodies in test tubes of 
