226 PROCEEDINGS OF THE AMERICAN ACADEMY. 



Mucor neglectus Vuillemin. 



In this species Vuillemin ('87) found no zygospores. His figures, how- 

 ever, represent azygospores formed at the ends of recurved branches. 



Thamnidium mucoroides Zukal. 



This species was found by Zukal ('90) on a moist culture of alligator 

 dung. Not infre(j;uently four to live zygospores are formed in a scalariform 

 fashion between two filaments. The zygospores are formed in the sub- 

 stratum and in the air, but sporangia are not developed from the same 

 hyphae. " The simultaneous occurrence of sporangia and zygospores 

 shows that the alternation of sexual and nonsexual generations has 

 been practically obliterated, and is only indicated by the fact that from 

 zygospores are developed only sporangia, or a sporangium producing 

 mycelium." This is not a Thamnidium, and A. Fischer ('92) rightly 

 places it among the cymose Mucors. 



Mucor rubescens Leger. 



The zygospores of this species, which was discovered by Leger 

 ('96) p- G9) on beer wort, are said to occur only in the interior of the 

 substratum. 



Mucor geophilus Oudemans. 



This form of Oudemans and Koning ('oi, p. 13) was obtained from a 

 separation culture of forest humi>s. The zygospores as figured appear 

 to be merely large chlamydospores. 



Mucor I Winkler. 



This form, experimented on by Winkler ("02), was cultivated from 

 forest earth. " It is a cymo-mucor, very similar to Mucor altemans, 

 except tJiat it forms zygospores abundantly on wort gelatine." 



Mucor alpinus Hansen. 

 Mucor neglectus Hansen (not Vuillemin, nor Bainier). 



These two species were obtained by Hansen ('02) from soil, the first 

 from the Alps, the second from the Harz Mountains. His M. ucf/lectiis 

 differs from M. alpinus in that the zygospores are produced two days 

 earlier than the sporangia, and the maximum temperature for their 

 development is higher than for that of the sporangia, while the reverse 

 is true in both respects of M. alpinus. Numerous cultures were appar- 

 ently made in investigating the capacity of these forms to produce yeast 



