2i0 GRASSES OF IOWA. 



Rabenhorst and found by Caspary.* The writer has published 

 several notes on this fungus, f It is closely allied to several 

 species of Helminthosporium. Mr. Ellis, to whom specimens 

 were submitted, writes that the fungus is, without doubt, Raben- 

 horst 's ^eZmmi/iOS'pormmg'ramim^m and this is the same as H. 

 inco7ispicuum,l C. & E. and Passerini's H. turcicum.% The speci- 

 mens in Ellis North American fungi were found on dead 

 leaves of Zea mays. Passerini's specimens were also found on 

 the species and he attributed it to the fungus he has described. 

 Briosi andCavara|| have described, figured, and distributed the 

 same fungus in their collection of parasitic fungi. The 

 spores of these species seem to agree well enough with Raben- 

 horst's H. gramim(m,'ii which was found by Caspary on barley. 

 Prank**, in his earlier work on the parasitic diseases of plants, 

 considered it to be only a well developed Cladosporium, but 

 later refers it to Helminthosporium. In 1885, Erikssonff found 

 a disease on barley, near Upsala and Stockholm, which he 

 considered identical with that found by Caspary on barley in 

 Germany. KirchnertJ; reports it as common in Germany and 

 gives a good account. Later Aderhold§§ reported on its common 

 and destructive occurrence in Silesia. 



The Iowa barley disease agrees with Eriksson's, but diifers 

 from the corn disease found by Passerini. According to the 

 latter observer the leaves of corn affected by the fungus are at 

 first yellow, then become more or less discolored and finally 

 wilt. 



The spots in the specimens distributed by Briosi and Cavara 

 on corn are sharply limited and extend across the veins. This 

 disease manifests itself long before the barley has headed out. 

 In the barley disease the spots extend from the base to the 

 very tip of the leaf in parallel rows. The diseased leaves form 

 quite a contrast to those of adjoining healthy plants, as they 

 are variegated pale yellow and green. All the stalks of a stool 



♦Herbarium mycologicum. 3X'. 



tPammel. Fungus diseases of Iowa forage plants. Pammel. .Tour. Myc. 7: 96. See 

 alsoSorauer. Pflanzenkranlchelten. 348. Tubeuf. Pflanzenliranl^heiten. 531. 



*EIlis N. Am. fungi. No. ■I'k Grevillea. 6: 88. 



§La nebbia del granturco. 3. Schroeter. Just Bot. Jahresb. 1878: 184. Comes. Critto- 

 gamia agraria. 1 : 409. 



ilFungi Parassltl delle piante cultivate od utili essicatl deliniati e descritti. Fasc. 

 Ill and IV, No. 81. 



1; Herbarium mycologicum. 332. 



**Krankheiten der Pdanzen. 583. (Ed. 1.) 316. (Ed. 3.) 



ttUeber eine Blattfleclienlcranliheit der Gerste. Bot. Centralbl. 29: 89. Sorauer .lust 

 Bot. Jahresb. 1885: 515. Distributed InFangi Scand. 187. 



itBraunfleclfigkeit der Gerstenblatter. Zeitsch. fur. Pflanzenk. 1 : 34. 



§§Zeltsch. fur. Pflanzenk. 5: 10. 



