Economic Importance of Plants 253 



disease) characterized by suppurative and granulomatous lesions any- 

 where in the body but especially in the skin, lungs, and bone. The causal 

 organism is a spherical, budding, yeastlike fungus. (B) The pathogenic 

 yeastlike fungus (Candida [Monilia] albicans) (Fig. 74, B) causes a 

 great variety of acute or subacute infections known as moniliasis in which 

 lesions may be present in the mouth, skin, vagina, nails, or lungs, and 

 even a septicemia, endocarditis, or meningitis. When the mouth is in- 

 fected there are produced creamy-white patches of ulcers, and this dis- 

 ease is called thrush. The causal organism is a budding, yeastlike, 

 mycelium-producing, nonascospore-forming, fungus. (C) The patho- 

 genic fungus (Coccidioides immitis) (Fig. 74, C) causes a very common 



Fig. 74. — Pathogenic fungi, not drawn to scale and somewhat diagrammatic. 

 A, Blastomyces dermatitidis, showing yeastlike budding cells; B, Candida (Monilia) 

 albicans, showing yeastlike cells and hyphae; C, Coccidioides immitis, showing 

 branching hyphae segmented into thick-wailed arthrospores, and a thick-walled 

 spherical structure (upper right) filled with endospores ; D, Sporotrichum schenckii, 

 showing branching, segmented hyphae with clusters of terminal conidia; E, Epi- 

 dermophyton floccosum, showing hyphae with clavate, multiseptate macroconidia; 



F, Trichophyton sp., showing hyphae with numerous single-celled microconidia; 



G, Microsporum sp., showing hyphae with large multicellular macroconidia 

 (above) and small, unicellular microconidia (below) ; H, Actinomyces bovis, 

 showing delicate, branching filaments, very much like those of certain bacteria 

 such as Mycobacterium tuberculosis. (From various sources.) 



infectious disease known as Coccidioidomycosis which may be of two 

 types: (1) primary (usually acute but benign self-limited respiratory 

 infection) and (2) progressive (chronic malignant infection involving 

 the skin, internal organs, or bones) . The causal organism is a fungus 



