HISTORICAL 5 



and Broome (1881, 1882), Spegazzini (1895-1896), Cooke (1871 to 1891), 

 and even Saccardo, all of whom were active, primarily as collectors, and 

 brought to light many species of real value among groups which make more 

 satisfactory herbarium specimens. The assumption that whatever was 

 found in nature undisturbed by man was normal early became dominant 

 and still persists in much of the taxonomic literature. 



Many years were required for mycologists to reahze that among these 

 molds, much of what we now loosely call morphology, represents response 

 to environment. For example, a mold gro^\^l in the presence of a ferment- 

 able sugar may show one aspect; whereas, the same mold, if gro\vn on a 

 leather shoe or some other nitrogen-rich substrate, may assume a very 

 different appearance. If gro^^^^ in mixtures with other molds and bacteria, 

 the colonies of a particular culture often lose identifying characters based 

 upon its development in some other environment. Thus, the idea of 

 gro^\'ing molds in pure culture under standardized conditions as a basis for 

 taxonomy gradually developed. 



DeBary's laboratory began to report work with cultures of molds be- 

 tween 1850 and 1860. It was not, however, until Brefeld pubHshed the 

 life history of "Penicillmm glaucum" in 1874, that real cultural study of 

 the Penicillia was initiated. He limited the discussion to one species, 

 P. glaucum, which is nowhere in his paper fully described, although struc- 

 tures encountered at each stage of its life history were described in detail 

 and elaborately figured. Part of these figures show evidence of being 

 drawn from actual preparations; others are obviously schematic and pre- 

 sent Bref eld's interpretation of his observations. The method of conidium 

 formation was evidently not understood, but the general structure of the 

 penicillus was beautifully developed. The formation of perithecia as 

 hard sclerotium-like masses of pseudoparenchyma, followed by the slow 

 development of ascogenous central areas, was described and illustrated, 

 although such were not to be unmistakably reported again until the studies 

 of Dodge (1933), van Be>Tna (1929, 1933), and Shear (1934), more than 

 fifty years later. Brefeld states that he was working with the "common 

 P. glaucum," which is generally interpreted as approximating P. expansum 

 Link as we know this species today. His work was done with the cruder 

 methods of culture which preceded the rise of bacteriology with its pro- 

 vision for protecting cultures against contamination, hence it is not sur- 

 prising if the various drawings presented suggest the probability that 

 more than one species was involved in his series of cultures. One of his 

 figures, depicting a coremium from a rotting pear, apparently represents 

 some strain of P. expansum; and the figures of some of his penicilli closely 

 approximate this species except that conidia are generally elliptical (fig. 

 7B) rather than globose as shown in Brefeld 's figures (fig. 2). The peri- 



