96 ZYGOMYCETES. 



Sub-Class 2. Basidiomycetes. 

 Series 1. Protobasidiomycetes. Partly gymnocarpic, partly 



angiocarpic. 



Series 2. Autobasidiomycetes. 

 Family 1. DACRYOMYCETES. Gymnocarpic. 

 Family 2. HYMENOMYCETES. Partly gymnocarpic, partly hemi- 



angiocarpic. 



Family 3. PHALLOIDEJE. Hemiangiocarpic. 

 Family 4. GASTEROMYCETES. Angiocarpic. 

 Additional : BASIDIOLICHENES. Lichen-forming Basidiomycetes. 

 Additional to the Fungi : FUNGI IMPEBFECTI. Incompletely known 

 (Saccliaromyces, Oidium-iorms, etc.). 



Class 1. Phycomycetes (Algal-Fungi). 1 



This group resembles Vaucheria and the other Siphonese among 

 the Alg83. 



ORGANS OF NUTRITION. The mycelium is formed of a single cell, 

 often thread-like and abundantly branched (Fig. 78). Vegetative 

 propagation by chlamydospores and oidia. Asexual reproduction 

 by endospores (sometimes swarmspores) and conidia. Sexual re- 

 production by conjugation of two hyphae as in the Conjugate, or 

 by fertilisation of an egg-cell in an oogonium. On this account 

 the class of the Phycomycetes is divided into two sub-classes : 

 ZYGOMYCETES and OOMYCETES. 



Sub-Class I. Zygomycetes. 



Sexual reproduction takes place by zygospores, which function 

 as resting-spores, and arise in consequence of conjugation (Fig. 81); 

 in the majority of species these are rarely found, and only under 

 special conditions. The most common method of reproduction is by 

 endospores, by acrogenous conidia, by chlamydospores, or by oidia. 

 Swarmspores are wanting. Parasites and saprophytes (order 6 and 7). 

 The zygospores are generally produced when the formation of 

 sporangia has ceased; e.g. by the suppression of the sporangial- 

 hyphce (Mucor mucedo}, or by the diminution of oxygen; Pilobolus 

 cnjstallinus forms zygospores, when the sporangia are infected 

 with saprophytic Piptocephalis or Pleotrachelus. 



A. Asexual reproduction only by sporangia. 



Order 1. Mucoraceae. The spherical sporangia contain many 

 spores. The zygospore is formed between two unicellular branches 

 (gametes). 



1 Also termed Water-Fungi (Wasserpilzen). 



