244 



APPLIED BACTERIOLOGY 



hjlliJiw or thallns. It is from these organs that the moulds 

 derive their name of hypomycetes. Some hyphie form large 

 round or cylindrical mother-cells, or sjinfaniiia, in the in- 

 terior of which spores are formed by endogenous formation. 

 According to the form of the seed-bearing organ, the moulds 

 are divided into four divisions, viz., Mucorinece, Aspenjil- 

 liiue, PcnicilliacciC, OidiaciKe. 



1. Mucorineae. — In the niucors, or headed moulds, the ends 

 of the hyphfe swell into knobs known as columella, around 

 which a seed-capsule or sporangium forms. When ripe, the 

 spores burst the enclosing membrane, and thus become free. 



Fig. 1'). — MucoE Mucedo. 



'"ina?, or knob-moulds, have 

 30vered with a number of 

 m the extremities of which 



liacea?, or pencil moulds, 

 differ from the two former varieties by forming branched 

 hyphie, known as hasidia, on the terminals of which are 

 seen the sterigmata, from which the conidia, or spores, are 

 separated in the form of chains. 



4. OidiaceaB. — The hyphfe of the Oidiacese form no 

 special spore-bearing organs, but the hypha become 



