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COMPARATIVE MORPHOLOGY OF FUNGI 



laterally, arise four, occasionally five or six, protuberances which become 

 ellipsoidal, sessile spores (Fig 273, 1 and 2). In damp weather they 

 germinate while on the basidium without being ab join ted, and each 

 forms a short germ tube (Figs. 273, 3 and 4; 274, 8 and 9) which may 

 branch and swell terminally to a conidium, slightly curved and pointed 

 at the end. The conidia abjoint and germinate immediately, in T. 

 helicospora by further sprouting. In T. deliquescens, the basidiospore, 

 the germ tube and conidia are uninucleate; in T. thelephorea, the basidial 

 nucleus, immediately after its entrance into the spore, passes through a 

 third division (Fig. 274, 7); hence its mycelium is wholly binucleate 

 (Brefeld, 1889; Juel, 1897, 1898, 1915; Raunkiaer, 1918). 



Fig. 274. — Tulasnel la thelephorea. 1 to 5. Development of basidia. 6. Basidium with 

 four basidiospores. 7. Caryogamy in the basidiospores. 8, 9. Germination of basidio- 

 spores with conidium. (1 to 7, 10, 11 X 535; 8, 9 X 355; after Juel, 1897.) 



The above interpretation of the reproductive organs follows that of 

 Juel. Patouillard (1888) regarded the "basidia" of the above descrip- 

 tion as probasidia, the "spores" as basidia, the "germ tubes" as sterig- 

 mata and the "conidia" as basidiospores. The spores were regarded as 

 the four separate cells of the cruciate basidium and hence related to the 

 Tremellaceae. Neuhoff (1924) revives this conception, replacing the 

 probasidium by the term hypobasidium and the cruciate basidium by 

 epibasidium. Hoehnel and Litschauer report that there is a complete 

 series of transitions between the slender sterigmata of the Corticiaceae 

 and the "spores" of Tulasnella and consequently regard the sessile 

 spores, which are never ab jointed, as swollen sterigmata and the conidia 

 as true basidiospores. Raunkiaer (1918) and Burt (1919) agree with 

 this conception and the latter places Tulasnella in the Thelephoraceae 

 (sensu latiore) near Aleurodiscus, where the sterigmata are often swollen 

 at the base. 



