72 BOTANICAL GAZETTE [January 



the intervening portions of filament wall merely collapse as the 

 spores mature. ScHtJTZE believed that these intervals were filled 

 with attenuated protoplasm, and that by their constriction the 

 spores were delimited without the evacuation of portions of hyphal 

 wall. The spore of Neukirch, consequently, is a structure possess- 

 ing its own spore wall, enveloped, except at its ends, by the rem- 

 nants of the old filament wall; that of Schutze, on the other hand, 

 is without a separate spore wall, the filament wall constituting the 

 only membrane present, and forming a spherical shell everywhere 

 inclosing the protoplasm. 



Neukirch gave much attention to certain structures he desig- 

 nated as oidium-spores. They developed in submerged growths, 

 the transformation of the filament consisting only in more or less 

 close septation, followed by a slight swelling of the segments. 

 Under suitable conditions filaments grew out from them, an 

 occurrence Neukirch regarded as germination. " Aussenplasma " 

 and "Innenplasma," in his opinion, were sharply defined, but a 

 spore wall was absent. The elements did not exceed the filaments 

 in resistance either to heat or desiccation. Neukirch believed 

 their function to be the dissemination of the fungus in liquid media. 



Lachner-Sandoval seems to have seen the same structures 

 and regarded them as segmentation spores that had developed in 

 the submerged condition. Gilbert, Schijtze, and Krainsky (id) 

 record their failure to find these bodies without, however, denying 

 their existence. According to Schijtze and Gasperini, sporulation 

 may occur in hyphae which are not truly air hyphae. 



It seems questionable whether any desirable end is served by 

 calHng Neukirch's elements spores at all. To apply the term 

 to structures with so little individuahty, even though a sort of 

 promiscuous viability may be attributed to them, is approaching 

 very close to the point where all bodies not filaments of uniform 

 thickness are to be regarded as spores. Certainly the distended 

 elements in old mycelium of Actinomyces VIII (figs. 47, 48), which 

 represent enlargements of axial filaments developed gradually in 

 the course of time at the junctures with moderately complex systems 

 of sporogenous hyphae, frequently have an equal or greater resem- 

 blance to reproductive bodies; and the behavior, under similar 



