Chapter VIII 

 ASYMMETRICA 



Included in this section are all of the Penicillia which produce conidial 

 structures consisting of two or more series of cellular elements (i.e., sterig- 

 mata, metulae, and branches), and in which the branching system is 

 typically irregular, one-sided, or asymmetrical. The elements comprising 

 such penicilli develop ordinarily in basipetal succession, i.e., the first group 

 of sterigmata develop upon the tip of the main axis, then a verticil of me- 

 tulae develops from the next lower node or septum, and branches, when 

 present, arise successively lower down on the conidiophore. Since these 

 branching elements are, as a rule, incompletely verticillate, the penicillus 

 appears more or less one-sided, or asymmetrical, in arrangement. 



The general type of penicillus described is an arbitrary common character 

 that brings together several more or less well-defined groups, which we 

 consider as Sub-sections. Each of the sub-sections embraces two or more 

 series which, for the most part, are believed to represent natural groupings 

 of species and strains. They are differentiated upon the general pattern 

 of the penicillus and the character of the aerial growth, with particular 

 reference to the origin and arrangement of the conidiophores. Five 

 sub-sections are recognized as follows: 



DivARicATA, characterized by strongly di\aricate penicilli, often pre- 

 senting the overall aspect of an irregular and terminal cluster of mono- 

 verticillate structures. 



Velutixa, usually producing penicilli that are once- or twice-branched 

 below the level of the metulae, and characterized particularly by the 

 development of abundant conidiophores in a dense stand from the sub- 

 stratum or a basal felt to produce a conidial layer that is velvety in 

 appearance. 



Laxata, producing penicilli much like the preceding, but characteris- 

 tically developing a loose-textured or floccose aerial mycelium, and 

 producing conidiophores largely from this aerial growth. 



FuNicuLOSA, producing penicilli of the same general pattern as above, 

 but with the aerial growth commonly showing a definite to conspicuous 

 ropiness, and with conidiophores commonly arising from such ropes or 

 fvmicles. 



Fafciculata, producing penicilli much like the preceding, but with 

 conidiophores arising almost cxclusivel.y from a submerged mycelium 

 and characteristically aggregated into tufts, fascicles, or coremia. 



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