922 RECORD OF CURRENT RESEARCHES RELATING TO 



Protomyces graminicola,* — Dr. Schrceter has detected tliis fungus, 

 recently described by Saccardo, in great quantities on Setaria viridis 

 and S. glauca, and finds it identical with Ustilarjo Urhani Magnus. He 

 considers it an endophytic Phycomycete, belonging either to the 

 family Peronosporese or Pythiaceae. 



The fungus was especially abundant on the above-named grasses 

 where they constituted the most abundant weeds in potato-fields ; and 

 in this situation Schrceter found on Setaria a conidia-bearing fungus, 

 the identity of which with the one in question he could not doubt. 

 This corresponded very closely with the smaller sjiecies of Peronospora, 

 such as P. pygmcpa, but was distinguished by the acute ends of the 

 branches. He considers the fungus to be therefore a true Peronospora, 

 but belonging to a new section, which he calls Sclerospora, distin- 

 guished by the unequally thick dark-brown envelope consisting of 

 several layers, formed out of the oogonium wall, and the dusty spores. 

 With the exception of P. Schleideniana on Allium Cepa, this is the only 

 Peronospora hitherto detected parasitic on a monocotyledon. Schrceter 

 thinks that the parasite may be of economical value from its destruc- 

 tive influence on very widely distributed agricultural weeds. 



Conidial Fructification in Mucorini.f — Di". Cunningham describes 

 the complete life-history of Choanepliora, a mucedinous fungus, para- 

 sitic on the corolla of Hibiscus and other shrubs in India, including 

 no less than four distinct forms of fructification. Of the reproductive 

 bodies one kind, tlie zygospores, are sexual, and the other three non- 

 sexual: — conidia, sjwrangial spores, and chlamydospores. The sj)oran- 

 gial and chlamydosporic reproductive bodies appear to be more closely 

 allied to one another than to the conidia. They are new and inde- 

 pendent cells formed within the tubular system of the parent plant ; 

 but the conidia are merely isolated portions of that system, being, in 

 fact, only the tips of the terminal filaments of the aerial portion of 

 the plant. The distinction is not merely an anatomical one ; the fact 

 that the difference in the nature of the conditions favours the develop- 

 ment of the various forms of fructification, indicates a physiological 

 distinction also. The conidial fructification is the form characteristic 

 of active nutrition and vegetative growth. Given a very rich nutritive 

 medium and fully developed normal conidia, a luxuriant development 

 of mycelium occurs, followed, sooner or later, by an abundance of 

 conidial fructification. With diminishing nutrition there is progres- 

 sively poorer mycelial development and less-developed conidial fruc- 

 tification. When this degeneration has reached its utmost limit, when 

 the conidial fructification is reduced to its poorest and simplest type, 

 the sporangia begin to make their appearance ; and when the con- 

 ditions of nutrition are too greatly lowered even to allow of this, we 

 find the chlamydosporic fructification providing for the preservation 

 and dift'usion of the plan. 



Dr. Cunningham's observations are in one point inconsistent with 

 those of Van Tieghem and Le Monnier, who deny that true conidial 

 fructification ever occurs in the Mucorini ; and the conjunction of 

 these various forms in one species would destroy Brefeld's proposed 



* ' Hedwigia,' xviii. (1879) p. 83. 



t ' Trans. I.inn. Soc. (But.),' i. (1879) p. 409. 



