298 PROCEEDINGS OF THE AMERICAN ACADEMY. 



which are associated with the imperfect forms of many of the higher 

 fungi, may bear a close resemblance to bulbils. Although compound 

 spores may in general be distinguished by the fact that they normally 

 arise as the result of the septation of a single cell, while in the pro- 

 duction of bulbils two or more cells are primarily involved, to which 

 others are added by a process of budding which may also be combined 

 with secondary septation, it is not always possible to separate them 

 with certainty. Spores like those of Stephanoma, referred to else- 

 where, in which the empty superficial cells arise by budding, serve, 

 however, to break down this distinction. 



On the other hand, the more complicated types of bulbils are easih^ 

 comparable to the simpler types of sclerotia, such as occur for example 

 in Penecillium Italicum, VcrticiUium agaricinum and similar forms. 

 Such sclerotia, however, result from the irregular and indefinite 

 massing together of vegetative filaments, the densely compacted 

 cells of which do not partake of the nature of spores, while the func- 

 tional cells of bulbils are usually spore-like and act independently of 

 one another at the period of germination. 



Among the compound spores formed in connection with the imper- 

 fect conditions of higher fungi, several may be mentioned which have 

 bulbil-like characteristics. 



Stephanoma slricjosum Wallr. a parasite on Pczha hcmispherica 

 which, as Dr. Thaxter informs the writer, occurs also on Genoa 

 hispidula in this country and is connected with an undescribed hypo- 

 creaceous perithecial form, might very well be regarded as a bulbil of 

 a simple type, since not only are its spores similar in their develop- 

 ment, but, when mature, are hardly distinguishable from the more 

 simple bulbils which are often produced, for example, by Papulospora 

 parasitica. 



Stemphi/Iium macros poroidewn Sacc, which has been examined from 

 cultures kept in the Cryptogamic Laboratories, produces a compound 

 spore consisting of one large functional cell to which, at maturity, two 

 or more empty ones are attached. In this condition it resembles very 

 closely the bulbil of AcrosjMira viirabUis; but in \iew of the fact that 

 it develops as a result of the successive divisions of a single terminal 

 cell, it must be regarded as a compound spore. Certain other forms 

 also of Stemphylium as well as of Mystrosporium might well be mis- 

 taken for bulbils. 



Hyalodcma Evansii P. Magn., which von Hohnel has referred to 

 Coniodyctium Chevalieri H. & Pat., produces a hymenium-like layer 

 bearing compound spores which, except in color, are very like the 



