198 THE HIGHER FUNGI : CARPOMYCETEAE 



The ultimate reproductive cells of the spore fruit are the basidiospores or sporidia, 

 borne externally on a cell called the basidium which was originally a 

 dicaryon cell in which the two nuclei united, or on the outside of a group 

 of four cells produced by the division of, or as an outgrowth from, the 

 cell with the diploid nucleus. About 32,000 species have been described. 

 With considerable reluctance the author follows the practice of most 

 mycologists and includes the Class Teliosporeae of the first edition of 

 this textbook as a distinct subclass within the Class Basidiomyceteae. 

 The teliospore characteristic of this subclass originates as a dicaryon cell 

 whose nuclei unite. From this cell grows out a thin-walled, usually four- 

 celled, filament, the promycelium, upon whose cells are borne the sporidia. 

 The limits of this subclass coincide rather closely with the Hypodermii 

 which form Order IV of Class IV, Coniomycetes, of Elias Fries (1832). 

 Ascus, teliospore, and basidium appear to be liomologous structures, 

 originating as binucleate cells in which karyogamy occurs, followed by 

 reduction division of the fusion nucleus, the nuclei thus formed becoming 

 the nuclei of the ascospores, sporidia, or basidiospores, respectivel3^ 



Class Basidiomyceteae 



In addition to these classes there is another class, the Fungi Imperfecti, often 

 called Deuteromyceteae, consisting of fungi whose vegetative structures 

 or mode of asexual reproduction show their relationship to the Higher 

 Fungi, but which lack any sexual type of reproduction or structures sub- 

 stituted for such sexual reproduction. Perhaps the majority are asexual 

 stages of Ascomyceteae though some are undoubtedly corresponding stages 

 of Basidiomyceteae. Until the perfect (sexual) stages can be found, their 

 true relationship cannot be ascertained. About 32,000 species have been 

 recognized. Class Fungi Imperfecti 



Literature Cited 



Bessey, Charles E.: An enormous puff-ball. Am. Naturalist, 18(5) :530. 1884. 

 : A synopsis of plant phyla, Univ. (Nebraska) Studies, 7(4):l-99. PL 1. 



1907. 

 Bessey, Ernst A.: Die Bedingungen der Farbbildung bei Fusarium, Flora, 



93(4) :301-334. 1904. 

 Brodie, Harold J.: Protoplasmic continuity in the powdery mildew, Erysiphe 



graminis DC, Can. J. Research, C, 20:595-601. PL 1. and Figs. 1-9. 1942, 

 Buller, a. H. Reginald: Researches on Fungi: vol. 1, xi + 287 pp., 5 pis. 83 



figs., 1909; vol. 2, xii + 492 pp., 157 ^^s., 1922; vol. 3, xii + 611 pp., 227 figs., 



1924; vol. 4, xiii + 329 pp., 4 pis., UQfigs., 1931; vol. 5, xiii -f 416 pp., 174 



figs., 1933; vol. 6, xii -|- 513 pp., 231 figs., 1934. London, Longmans, Green 



and Company. 

 Clements, Frederick E. : Minnesota Mushrooms, Minnesota Plant Studies IV, 



169 pp. 124: figs. Univ. Minnesota, 1910. 

 Fries, Elias: Systema mycologicum, sistens-fungorum ordines, genera et species 



hue usque cognitas, vol. 3, ^•iii -{- 524 pp., index 200 pp. Greifswald, Ernest 



Mauritius, 1829-32. 

 Heim, Roger: Observations sur la flora mycologique malgache: HI. Trois bolets 



gigantesques d'Afrique et de Madagascar, Rev. MycoL, N.S., 1(1):3-18. Pis. 



1-4. 1936. 

 Honey, Edwin E.: North American species of Monilinia: I. Occurrence, grouping 



and life histories. Am. J. Botany, 23(2):100-106. Figs. 1-4. 1936. 



