164 RESEARCHES ON FUNGI 



in such bad condition that I was unable to determine whether or 

 not they were tremelloid in character. 1 The discovery of Tremel- 

 lineae with gills cannot therefore be said to have been definitely 

 made up to the present. 



The basidia of the Tremellineae differ in structure from those 

 of the Thelephoreae, the Clavarieae, the Agaricineae, the Poly- 

 poreae, and the Hydneae. Whereas in these five last-named 

 groups of Hymenomycetes the basidia are clavate and unicellular, 

 in the Auricularieae the basidia are elongated, cylindrical, and 

 transversely septate ; 'in the Tremelleae the basidia are more or 

 less globose and divided into four cells by two crossing vertical 

 partitions ; and in the Dacryomyceteae the basidia have two long 

 arms and are non-septate. The resemblance of various Tremellineae 

 to Stereum, Merulius, Hydnum, Clavaria, etc., cannot therefore 

 be due to direct inheritance, but must be accounted for by phylo- 

 genetic convergence taking place during the course of evolution. 

 The Tremellineae discharge their spores in the same manner as the 

 other Hymenomycetes and, in the struggle for existence, they have 

 been compelled to adopt the same efficient forms for the production 

 and liberation of their spores as we find in the Thelephoreae, the 

 Polyporeae, the. Hydneae, and the Clavarieae. The convergence 

 in form which has come about by the fruit-bodies of the Tremel- 

 lineae and of the non-tremelloid Hymenomycetes evolving along 

 parallel lines finds many analogies elsewhere, among which may 

 be mentioned (1) the convergence in dentition and habits of life of 

 the metatherian mammalia of Australia and the eutherian mam- 

 malia of Europe, Asia, Africa, and North and South America, and 

 (2) the development of cylindrical, so-called telescope-eyes by certain 

 fishes, Crustaceans and Cephalopods which inhabit the depths of 

 the sea. 2 



The basidia of the Tremellineae are somewhat different in 

 form from those of the non-tremelloid Hymenomycetes, and this 

 difference in form is doubtless accompanied by a corresponding 



1 C. G. Lloyd has named the fungus Phyttotremella africana and given some 

 illustrations of it in his Mycological Notes, September 1920, p. 1007, and Figs 1850- 

 1852. 



2 A Weismann, The Evolution Theory, translated by J. A. and M. R. Thomson, 

 London, 1904, vol. ii, p. 323. 



