Phylum Inophyla [ 149 



Order 3. Ustilaginea [Ustilagineae] (Tulasne and Tulasne) Winter in Rabenhorst 

 Kryptog.-Fl. Deutschland 1, Abt. 1: 73 (1884). 

 Ustilagineae Tulasne and Tulasne in Ann. Sci. Nat. Bot. ser. 3, 7: 73 (1847). 

 Subclass Hemibasidii Engler Syllab. 26 (1892). 

 Order Ustilaginales Bessey in Univ. Nebraska Studies 7: 306 (1907). 



The smuts: parasitic Basidiomycetes completing their development on a single 

 host, the dikaryophase mycelium breaking up into thick-walled black spores, these 

 functioning as probasidia, the basidia usually bearing more than four basidiospores. 



In the apparently more primitive smuts, the promycelia are four-celled phragmo- 

 basidia. The haploid nuclei divide before passing into the basidiospores, with the 

 effect that each cell of the promycelium buds off a series of basidiospores. In other 

 examples the promycelia do not become divided by walls, but are of the character of 

 holobasidia. The basidiospores of some species are capable of budding like yeasts. 

 In some species, they are capable of syngamy with each other, and in some they send 

 out hyphae which bear conidia of characteristic form. In many species, syngamy has 

 not been observed, but is beheved to take place between vegetative hyphae. Hybridi- 

 zation, and mutation, particularly in the capacity to attack particular races of hosts, 

 take place freely in smuts, which are accordingly well fitted to cope with the efforts 

 of plant breeders. 



The smuts are believed to be somewhat degenerate descendants of the rusts. 



There are two families, about thirty genera, about six hundred species. 



Family 1. Ustilaginacea [Ustilaginaceae] Cohn in Hedwigia 11: 17 (1872). The 

 basidia divided by transverse walls. Ustilago, on grasses and other plants. 



Family 2. Tilletiacea [Tilletiaceae] Dietel in Engler and Prantl Nat. Pflanzenfam. 

 I Teil, Abt. 1** : 15 ( 1900) . The basidia not divided by walls. Tilletia, on grains, etc. 

 Tuburcinia, Doassansia, the resting spores produced in globular masses. 



Order 4. Tremellina [Tremellinae] Fries Syst. Myc. 1: 2 (1821); 2: 207 (1822). 

 Order Tremellinei Fries Hymen. Eur, 1 (1874). 

 Order Tremellineae Winter in Rabenhorst Kryptog.-Fl. Deutschland 1, Abt. 1 : 



74 (1884). 

 Suborder Tremellineae Engler in Engler and Prantl Nat. Pflanzenfam. I Teil, 



Abt. 1**: iii (1900). 

 Order Tremellales Bessey in Univ. Nebraska Studies 7: 309 (1907). 

 Order Tulasnellales Gaumann Vergl. Morph. Pilze 487 (1926). 

 Saprophytic Basidiomycetes producing gelatinous fruits bearing a layer of basidia 

 which typically become divided into four cells by longitudinal walls. Each cell pro- 

 duces a long stout sterigma which reaches the surface of the fruit and bears a spore. 

 The mycelia, the young fruits, or the basidiospores may bear conidia. 



The number of species is perhaps one hundred. Nearly all belong to family Tre- 

 mellacea [Tremellaceae] Cohn in Hedwigia 11: 17 (1872). Martin (1935, 1937, 

 1939) has given much study to this group. It is clearly related to the Protobasidi- 

 omycetes; Patouillardina, having basidia divided by oblique walls, is clearly transi- 

 tional. Tremella, Sebacina, Tremellodendron, Hyaloria. 



Tulasnella differs from the generality of Tremellina in producing holobasidia of 

 a peculiar type, with bulbous sterigmata (Lindau interpreted the sterigmata as basi- 

 diospores borne without sterigmata and not released, but producing conidia; it may 

 be that this interpretation is more sound than the obvious one). It is supposed that 

 the holobasidia of this genus are derived from the cruciate basidia of proper Tremel- 



