Chapter I 

 HISTORICAL INTRODUCTION 



Historically, the Aspergilli, as a part of moldiness of things, have always 

 been a factor in man's environment, but for ages were brushed away as 

 white, yellow, green, red, or black mold, with or without any attempt at 

 interpretation. After the development of the microscope, men began to 

 see structure. Micheli (1729) distinguished conidiophores and heads. 

 He noted that the heads were rough, the spore chains or columns pro- 

 ducing an uneven surface, hence he gave the name Aspergillus (rough 

 head). He then marked with Latin phrases his sketches of differently 

 colored moldy substances, for example, Aspergillus capitatus ochroleucus, 

 probably some strain of Aspergillus ochraceus; Aspergillus capilulo pulla 

 for a black form, etc. Other authors followed, using much the same ter- 

 minology, but without illustrations definite enough to give knowledge of 

 the structure of the heads. Thus, Haller, in 1742, put what appears to 

 have been Sporodinia into the genus as A. ramosissimus, etc. There is 

 just about enough certainty in the use of A. albus, A. niveus, A. capilulo 

 pulla, A . purpureus, etc., to justify the continued use of the name Aspergillus 

 after taking out of the aggregate the extraneous material thrown into it 

 by the very scanty microscopic examination given by the early mycologists. 



Persoon (in the 1790's) threw the Aspergilli into his polyglot concept, 

 Monilia, based upon the production of spores in chains resembling strings 

 of beads. He made no record concerning their origin. Then Link in 

 1809 went back to Micheli and based his rejection of Monilia upon the 

 specification that these chains of spores must have their origin in a "head" 

 (capitulum) 



Link failed to examine that head closely enough to keep out questionable 

 forms although we know that in describing A. glaucus he had under his 

 microscope one of that group as it was found, then and now, upon partly 

 dried herbarium specimens. Correct interpretation of the structure of 

 this head appears first in the work of Corda who began, about 1828, to 

 publish his studies of fresh material, as seen under his microscope. Up 

 to about 1850 each worker was prone to look at his predecessor's descrip- 

 tions and figures, and either assign whatever he had to another man's 

 species, or conclude that each specimen he had was new and add another 

 group of names. Montagne complained (1856) that none of the descrip- 

 tions written before Corda were identifiable, while some of us are equally 

 uncertain of our ability to interpretMontagne. 



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