M. C. COOKE ON BLACK MOULDS. 247 



may peruse,* and the paper could only have been a skeleton of the 

 book. 



In order to interest, and, perhaps, to some extent, instruct the un- 

 initiated of the Club in a few of the mysteries of Fungology, I have 

 selected some examples from one of the six orders under which the 

 whole Fungi are classified ; and this order is termed Hy\>lwmycetes, 

 or " Thread Moulds," because the threads of which each individual 

 is comj^osed is the most prominent feature of the Fungus. 



Most microscopists have some knowledge of the general features 

 of such common moulds as Penicillin in and Aspergillus, in which 

 there are delicate branching threads forming a kind of root-fibrils, 

 and from these arise, rather more rigid and robust, erect threads, 

 which form a kind of stem ; and sometimes this stem becomes 

 divided into branches, the sides or tips of which are garnished with 

 little spha?rical or elongated spores, which are in reality the fruit. 

 In such a form as this we have the type of a " mould," a micro- 

 scopic tree or shrub, with root, stem, branches, and fruit, but with- 

 out either flower or leaves. It is such a type which prevails in the 

 Hyphomycetes, sometimes varied in one direction, sometimes in 

 another, but in all this variety there is unity, a unity of design 

 carried through a variety of patterns ; so that in obtaining a know- 

 ledge of a few of the forms in the order, we obtain a general clue to the 

 characteristics of the whole order, and, with the exception, perhaps, 

 of a few somewhat anomalous or intermediate forms, become 

 enabled at once to determine whether an unknown fungus, for the 

 first time under examination, belongs to this section or another, 

 which is so much knowledge acquired that may prove useful in future 

 microscopical studies. 



On the margin of this investigation, and before I proceed further 

 with the details, it may be well to address a few words to the 

 subject of the relative value and importance of physiological investi- 

 gations, and classificatory studies. 



In all branches of Natural History there are workers of two 

 kinds : those who investigate the structure, physiology, origin, and 

 development of a few forms, and endeavour to comprehend the 

 whole mystery of their existence, and relationship to other mani- 

 festations of vital force, and those who devote themselves almost 

 entirely to the study of the various forms in any one or more 



* Fungi, their Nature, Uses, &c, International Scientific Library, pub- 

 lished by H. Kiug & Co. 



