HYPHOMYCETES 



637 



and, under favorable conditions, sends out a branch which terminates 

 in a non-sexual sporangium. 



Among the higher molds, or mycomycetes, various methods of 

 sporulation occur, but sexual reproduction does not usually take place. 



One of the most commonly found genera is that of Penicillium. In 

 this form the mycelial threads are partitioned off, by many transverse 

 septa, into a number of separate cells. From these, hyphse, also sep- 

 tate, are given off. From the ends of these hyphae, germinating 

 branches arise which are known as conidiophores. These conidiophores 

 divide into two or three septate branches, the sterigmata. From the 



k=3 Z 9 



FIG. 146. MUCOR MUCEDO. 1. Sporangium, c. columella, m. sporangium 

 capsule, sp. spores. 2. Columella, after bursting of sporangium. 3. Poorly de- 

 veloped sporangia. 4. Germinating spore. 5. Emptying of sporangium. . (After 

 Brefeld.) 



ends of these, other sterigmata may be given off and from the tip of 

 each of these a single chain of spores or conidia are constricted off. 

 The result is an appearance not unlike a hand in which the wrist 

 represents the conidiophore; the metacarpal bones, the sterigmata; and 

 the fingers, the long streptococcus-like chains of conidia. 



Similar to and even more common than the penicillia are the varieties 

 known as Aspergillus. These forms, like the preceding, form delicate 

 mycelial meshworks from which branches or conidiophores about 3-10 

 mm. in length, arise. These develop club-shaped expansions at their free 

 ends and from these club-shaped expansions radially arranged sterig- 



