GYMNOSPORANGIUM. 



403 



6. globosum Pari. Aecidia on Pyrus Malus, P. communis, 

 Cydonia vulgaris, Sorhus americana, and species of Crataegus. 



G. nidus-avis Thaxt. Aecidia and pycnidia on Pyrus Malus, 

 Amelanchier canadensis, and .Cydonia vulgaris. On the red cedar 

 it causes the " bird's nest " deformation of the branch-system. 



6. speciosum Peck. On Jiinvperus 

 occidentalis. 



6. Gunninghamianum Barcl. On 

 Gypressus torulosa in the Himalaya. 

 Aecidia on Pyrus Pashia. 



The following genera do not occur 

 in Europe. Coleopuceinia, Ravenelia, 

 Alveolaria, Tricliospora. 



Ravenelia alone amongst these 

 contains parasitic species of import- 

 ance. They all occur on Leguminosae 

 and Euphorbiaceae in the warmer parts 

 of India, Africa, and America. '^ 



Ravenelia Volkensii Henn. has teleutospore-sori which appear 

 on " witches' broom ' deformations of the twigs of an Acacia in 

 Usambara. 



Rav. pymaea Lager, et Diet, produces its teleutospores on 

 malformed branches of Phyllanthus in Ecuador. 



Certain forms of Aecidium which cause deformation of species 

 of Acacia should probably be included in this genus (see p. 410). 



Fig. 240. — Cedar A-pplcs caused 

 by Gymnospm'angiuTii maci'opus, 

 (T. Tubeuf del.) 



Endophyllum. 



Teleutospores originate serially on cushions which are enclosed 

 in a peridium similar to aecidia ; on germination, a four-celled 

 promycelium is produced.^ Leaves of Euphorhia, Sedum, or 

 Sempo'vivuin inhabited by mycelium develop abnormally. 



Endophyllum euphorbiae-silvaticae (D. C.) (Britain). Accord- 

 ing to Winter, the peridia are regularly distributed over the 

 underside of the leaf of Euphorbia amygdaloides ; they have 

 white fissured margins either erect or somewhat turned back. 



'Dietel, "The Genus Ravenelia," Hedwigia, 1894. 



- The teleutospores of this genus might be described as aecidiospores which 

 produce promycelia. 



