ASCOCHYTA. 



473 



U8 



this fungus is injurious to Pisum sativum, Phaseolus vulgaris, 

 Vicia sativa, etc. It causes spots on leaves and pods, followed by- 

 drying up of the former and deformation of the latter. The 

 pycnidia appear as tiny points on the spots, and give out bicellular 

 cylindrical conidia. 



As. Boltshauseri Sacc.^ 

 This species was first observed 

 in Switzerland on bean {Plia- 

 seolus vulgaris). Leaves of all 

 ages become brown -spotted, 

 and premature defoliation may 

 follow. The spots are marked 

 by concentric zones, and bear 

 pycnidia. The conidia are 

 two- to three-celled, being 

 distinguished in this and by 

 their larger size from the 

 preceding species. 



The following species fre- 

 quent living leaves : 



Ascochyta tremulae Thlim. On 

 the aspen. 



A. metulispora, B. et Br. On leaves of the ash in Scotland. 



A. armoractae Fuck. On Armoracia rusticana (Horse-radish). 

 (Britain.) 



A. periclymeni Thum. On Lonicera Periclymermm. 



A. maculans Fuck. On Hed&-a Helix. 



A. EUisii Thum. On Viiis Lahrusca in America. 



A. brassicae Thiim. On Brassica oleracea. 



A. dianthi (A.S.). On Dianthus. (Britain.) 



A. pallor Berk. On Rubus Idaeus. (Britain.) 



A. viciae Trail. On Vicia sepium, etc. (Britain.) 



A. malvicola Sacc. On Malva sylvestris. (Britain.) 



A. graminicola Sacc. On various grasses. (Brit£||in.) 



A. scabiosae Rabh. On Knautia arvensis. 



A. nicotianae Pass. On Nicotiana Tahaccum. 



A. digitalis Fuck. On Digitalis purpurea. 



A. fragariae Sacc. has been found injurious to the strawberry crop in the 

 United States. 



A. aspidistrae given {Gardener's Chronicle, xvii., 1895) as a parasite on 

 Aspidistra in Britain. 



Fig. 295. — Aacoclnjta pisi on Pea. Enlarged 

 section of pycnidia, and still more enlarged 

 conidia. (t. Tnbeuf del.) 



' Boltshauser-Amriswell, Zeitschrift f. PJlanzenh-ankheiten, i., p. 135. 



