334 TEXT-BOOK OF FUNGI 



Amphispores, like uredospores, are one-celled, and have 

 several germ-pores, but the cell-wall is thicker, and as in 

 teleutospores, germination is delayed until after a period 

 of rest. This form of spore is known in only a few species, 

 mostly N. American forms. Amphispores are perhaps 

 most abundant in the widely distributed Pucdnia pruni. 



Teleutospores, as the name implies, are formed last in 

 the sequence of spore-forms enumerated, although in some 

 species teleutospores alone are produced, as in Pucdnia 

 malvacearum. Teleutospores vary considerably in structure 

 and number of component cells in different genera. In 

 Uromyces the teleutospore is one-celled, with a single germ- 

 pore at the apex; in Pucdnia^ two-celled; in Triphrag- 

 mium, three-celled; whereas in Phragmidium and Xeno- 

 dochus, the teleutospore consists of a chain of cells. The 

 one distinguishing constant feature of a teleutospore is the 

 immediate product of germination. This consists of a 

 promycelium tube of limited growth, which becomes four- 

 celled by the formation of transverse septa ; each cell then 

 bears a single secondary spore, promycelium spore, or 

 sporidium, as it has been variously named. On the other 

 hand, aecidiospores, uredospores, and amphispores on 

 germination produce ordinary vegetative hyphae, which 

 directly form mycelium. Teleutospores form sori which 

 rupture the epidermis, and are produced singly at the tips 

 of unbranched hyphae, except in the genus Uromydadium, 

 recently founded by M'Alpine, where the hyphae bearing 

 teleutospores are branched near the apex. 



Teleutospores, also called winter spores or resting- 

 spores, usually only germinate after a period of rest, and 

 the secondary spores produced give origin to the mycelium 

 from which the aecidial phase of the fungus originates the 



