88 MINNESOTA BOTANICAL STUDIES. 



Of the 199 species enumerated in the Sylloge Fungorum, 

 Fischer has shown that 70 are to be excluded. Fischer describes 

 100 species for Europe, and Schroeter estimates 130 for the 

 whole world. I regard this as a very liberal estimate. The 

 species described for other parts of the world, if subjected to 

 the examination which Fischer has given the European species, 

 would doubtless yield a large proportion of synonyms. Thus 

 8 species are described from North America, chiefly by Berke- 

 ley and Curtis. These were named at a time when, as Fischer 

 says, every form of Miicor mucedo on a new substratum received 

 a new name, and most of them will have to be assigned to Mucor 

 mucedo or Ascophora mucedo, if one can be sure that they de- 

 scribe anything. 



Van Tieghem, who was the first to treat the group exhaust- 

 ively, and to whom we owe most of our knowledge of its forms, 

 divided the family in 1875 ^ into five tribes. Dewevre following 

 him, and adding the Ghoanephoreae, not in the scope of Van 

 Tieghem's work, arranges them thus: 



1. Pilol)oleae; 2. Mucoreae; 3. Chaetocladieae; 4. Choaue 

 plioreae; 5. Mortierelleae; 6. Cephalideae. 



Other authors agree with this substantially, except that they 

 unite the PiUholeae and Mucoreae. 



Fischer divides the grouj), which he terms an order {Mucor- 

 inae), into four families (the Choaneplioreae being without his 

 range); Mucoraceae, Chaetocladiaceae, Mortierellaceae, and Cepha- 

 lidaceae. The first he subdivides into three sub -families: 

 Mucoreae, Piloholeae, and Thamnidieae. Schroeter divides into 

 five families: Mucoraceae, Mortierellaceae, ChoanepJioraceae, 

 Chaetocladiaceae, Piptocephalidaceae, and subdivides the first into 

 Mucoreae and Piloholeae. 



I propose the following arrangement, the reasons for which 

 will be explained presently: 



Family MUCORACEAE. 



(Order Mucorineae of German authors.) 



Sub-family 1. Mucoreae. 



Tribe Eumucoreae. 



Tribe Rhizopeae. 



Tribe Thamnidieae. 



Tribe Piloholeae. 



Vau Tiegliem. Ann. Sc. Nat. vi, 1:41. 1875. 



