EXDOMYCETACEAE 143 



interminirle. A pair of nuclei, one from each gametangium, 

 fuses, and the supernumerary nuclei remain non-functional and 

 disappear. The female gametangium then elongates into a sac- 

 cate structure. Meanwhile several successive nuclear divisions 

 take place, and numerous ascospores are formed by free-cell for- 

 mation. At maturity the ascus tip opens to emit a gelatinous 

 mass of ascospores and cytoplasm, attractive to flies and other 

 insects that serve as vectors. Ascospores are capable of imme- 

 diate germination to repeat the course of development. There 

 is evidence that the ascospores may at times develop partheno- 

 o^enetically. 



Closely related to these Ascoideaceae, and perhaps \\ithin the 

 same family, although placed in the closely related family Cocci- 

 dioidaceae by Dodge (1935), are several very important human 

 pathogens. Among them are Coccidioides ii/n/iitis, the cause of 

 "valley fever," Rhhwsporidhmi seeberi, the cause of polypoid 

 growths in the nose, ears, and eyes, and Histoplasma capsidatinn, 

 the cause of Darling's disease, a necrotic involvement of the 

 lymph nodes, intestines, liver, and spleen. 



Endomycetaceae. The few members that comprise the Endo- 

 mycetaceae are little kno\\n. Eremascits albidits, found years ag^o 

 by Eidam on malt and apparently not seen since, has pairs of 

 spirally wound gametangia w^hich fuse apically. At the point of 

 contact of 2 gametangia a globular ascus arises, in which 8 

 ascospores are delimited. 



Endoviyces decipieiis, found on decaying mushrooms, bears 

 pairs of lateral branches. These branches fuse, and Juel (1921) 

 found that, although 3 nuclear divisions occur in the ascus, only 

 4 ascospores develop. In culture the hyphae of this fungus be- 

 come segmented into uninucleate oidia, which on growth as^ain 

 become mycelioid. 



Endomyces mail causes a decay of ripe apples [Lewis (1910)]. 

 It produces conidia on short conidiophores. These conidia, in 

 turn, produce hyphae. The ascus develops from a single hyphal 

 branch that contains a single nucleus. Four ascospores are de- 

 veloped in this parthenogenetic ascus. 



Many important human pathogens are placed by Dodge 

 (1935) within the Eremascaceae Imperfectae, or detached conid- 

 ial forms of Eremascaceae, a family which some workers would 

 include among Endomycetaceae. These detached fun^i belong 



