476 MEDICAL MYCOLOGY 



morph exudative, scarlatinoid, or similar to erythema nodosum (subcutaneous 

 nodules). Recently Jauison and coworkers (1932) have presented the view 

 that lichen planus and perhaps psoriasis may be essentially allergic phenomena 

 following a chronic ringworm infection, as all cases of lichen planus and 80% 

 of the psoriatics examined reacted with an intradermal injection of a poly 

 valent dermatophyte serum. 



Key to Genera 



Closterospores incompletely 4-6-locular, coenocytic, germinating either by a single hypha from 

 each locule or each locule forming a single, uninucleate endospore; on glabrous skin 

 of old world monkeys, inoculable into guinea pig forming ectoendothrix lesions. 



Pinoyella. 

 Closterospores completely septate; colony velvety. 



Either spirals or nodular organs present on some media and well developed; lesions of 



the ectothrix type, hyphae not seen in the hair. Ectotrichophyton. 



Neither spirals nor nodular organs present. 



Closterospores thin-walled with blunt ends, aleurospores rare or absent in most 



species; chlamydospores rare; lesions of the glabrous skin and nails, not 



attacking the hair. Epidermophyton. 



Closterospores thick-walled with pointed ends, aleurospores present and well developed ; 



hair invaded by hyphae. 



Hyphae not disappearing from the hair but producing a sheath of small spores 



at the surface. Microsporum. 



Hyphae disappearing from the hair, their place showing in microscopic prepara- 

 tions as air bubbles, favic scutula in the hair follicle common and 

 characteristic. Achorion sect. Lophophyton. 



Closterospores absent, chlamydospores usually abundant. 

 Aleurospores abundant and characteristic. 



Colony velvety, arthrospores not conspicuous and characteristic. 



Lesions of ectothrix type with large spores, producing sycosis in man and dry 



squamous lesions in domestic animals. Megatrichophyton. 



Lesions of endothrix type, without inflammation or suppuration, common on man, 

 rare on domestic animals. Trichophyton. 



Colony moist, arthrospores present ; lesions of endothrix type. 



Lesions with suppuration in domestic animals but inoculable into man. 



Favotrichophyton sect. Eufavotrichophyton. 



Lesions with some inflammation in man, not easily inoculable into domestic 



animals. Favotrichophyton sect. Bodinia. 



Arthrospores common and characteristic, aleurospores rare or absent, no suppuration on 



the usual host. 



Colony velvety, lesions of the glabrous skin of man, inoculable with difficulty into 



experimental animals. Endodermophyton. 



Colony moist, yeastlike; lesions of the hair with favic scutula in man. 



Achorion, sect. Euachorion. 



PINOYELLA 



Pinoyella Castellani & Chalmers, Man. Trop. Med. ed. 3, 1023, 1919. 

 The type species is Pinoyella simii Castellani & Chalmers. 

 Mycelium dimorphic, closterospores incompletely 4-6-locular, coenocytic, 

 germinating either by a hypha from each locule, or by the formation of a 



