362 



THE FUNGI WHICH CAUSE PLANT DISEASE 



to rupture by longitudinal slits along the sides; peridial cells im- 

 bricate and often articulated, occasionallj^ hygroscopic, outer walls 

 smooth, rather thin, inner walls smooth, verruculose, verrucose, 

 rugose, or spinulose. jEciospores in basipetal chains with alter- 

 nate barren cells, enclosed in a peridium, globoid to broadly ellip- 

 soid; wall colored, verrucose, usually with numerous, scattered, 

 evident germ pores. 



III. Telia erumpent, naked, usually definite, variously shaped, 

 gelatinous and elastic at maturity, expanding considerably when 

 moistened. Teliospores chieflj' 2-celled, in some species 3, 4, or 



Fig. 263.- 



-GjTnuosporangium, spore masses just emerging. 

 After Heald. 



5-celled, by transverse septa; walls colored, of various thickness, 

 smooth; pores usually two in each cell, sometimes, 1, 3, or 4, vari- 

 ously arranged; pedicels hyaline, elastic, usually of considerable 

 length, cylindric, rarely carotiform, walls thick, the outer portion 

 swelling and becoming gelatinous to form a jelly-like matryx in 

 which the spores appear embedded. 



All of the species agree in possessing the same spore forms, 

 pycnia, secia, and telia which appear in the same sequence in 

 the different species; also, in the fact with two exceptions, that 

 the secia grow on pomaceous plants and the telia on Juniperus 

 (with few exceptions). 



