CHAPTER XXI 



SPOROTRICHEAE 



Mycelium branched, septate ; spores unicellular, usually solitai-y, never in 

 chains, borne either on very short and little differentiated sterigmata along 

 the hyphae or sessile. Conidiophores wholly undifferentiated. 



The genera included here are often included in a larger group, the 

 Botrytideae, in which the conidiophore is variously branched. These genera 

 form a transition from the highly developed blastospores and arthrospores 

 of the Eremascaceae Imperfectae to the better known genera of Hyphomycetes 

 in which the conidia are borne on specialized conidiophores. Vuillemin sought 

 to place in a separate group, those species in which there seems to be little 

 or no provision for the separation of the conidium from the conidiophore, 

 naming the group Aleurismeae from the genus AleHrHsma, and calling such 

 spores aleurospores instead of conidia. For the most part, his Aleurismeae 

 have already been discussed in the Gymnoascaceae Imperfectae. There are 

 still a few forms, in which the mycelium is wholly uninucleate, which grow 

 in the horny layer of the epidermis. It is possible that they represent a stage 

 in the life cycle of some of the dermatophytes, but none of the species have 

 been adequately studied. The other genera, Acremonium, Acremoniella, Sporo- 

 trichum, and Trichosporivm, are all found in the subcutaneous tissues or in 

 the internal organs. Most species in these genera are saprophytic on decaying 

 vegetable matter. The whole group badly needs monographic study. 



Key to Genera 



Conidia or aleurospores sessile on the mycelium, depending on the death of the mycelium for 

 liberation. 

 Mycelium and spores white or light colored; found in the horny layer of the epidermis. 



A leurisma. 

 Mycelium and spores black. Trichosporium. 



Conidia usually on .short sterigmata, not in the horny layer of the epidermis. 

 Conidia terminal on sliort, simple, lateral branches. 



Conidia hyaline or bright colored. Acremonium. 



Conidia black or dark brown. Acremoniella. 



Conidia on long sterigmata, lateral on somewliat branched conidiophores. 



Bhinotrichum. 

 Conidia on short, simple hyphae or lateral or terminal, on short branches. 



Sporotrichum. 



ALEURISMA 



AleuHsma Link, Mag. Ges. Naturf. Freunde Berlin 3: 18, 19, 1809. 

 Blastomyces Costantin & Rolland, Bull. Soc. Myc. France 4: 153-157, 1888. 

 Aleurophora Magalhaes, Brasil Med. 30: 369, 370, 1916. 



786 



