402 



UREDINEAE. 



6. EUisii Berk. On Chamaccyparis fhyoidrs. The aecidial 

 stage on 7'//r//.s Malm and P. arhutifolia. 



On red cedar (Junipcrus virginiana) : 



G. macropus Lk. The aecidia and pycnidia occur on Fyrus 

 Mains, P. coronaria, P. ai-hvtifolia, Crataegus tomcntom, C. 

 Douglasii, and Amelanchicr canadensis ; they are known as 



Fig. 237.— Spores of 

 Gyra. Imeptatum. (After 

 Woernle.) 



Fio. 238.— Spores of 

 Gim. EUisii. (After 

 Woernle.) 



Fkj. 230.— Spores of 

 (Jt/M. iiiacropv.it. (After 

 Woernle.) 



Roestelia pirata. This is one of the commonest causes of 

 apple-rust and of the deformation known as " cedar apples " (Fig. 

 240). The anatomy of the latter structures has been described 

 by Sanford.^ 



G. clavipes Cooke et I'eck, occurs on Ji'niprrus coimmmis. 

 Its aecidia and pycnidia are found on Pyrus Mains, P. arhnti- 

 folia, and AmclancMcr canadensis. 



' Sanforcl, Amialx of Botcuiy, i., 1SS7. 



