309 



1430. Puccinia poarum Nielsen 76 a ''^^ 6. 77 a ^^ c. icon., Sydow 

 04^'^ Syn: Lycoperdon epiphyllum Miiller 1767^" partim, Aecidium 

 tussilaginis Pers. Syn. '"'^ Schum. no 1524, Fl. D. tab. 1366, Hestehovs 

 St0vskaal (H 37'°=), Falfod-Graesrust (R 93 c«' 6. 02 a^^*, M. L. M. 

 Juli 10), Rapgraesrust (R 04 a ^^). 



By his well-planned and carefully executed cultivating experiments 

 P. Nielsen has proved the relation between the aecidia on Tussilago 

 and St. II— III on Poa; st. II will always appear ten days after the 

 sowing of aecidiospores and the teleuto-stage 6—28 days later. 



P. Nielsen is of opinion that the first developed teleutospores in- 

 fect the leaves of Tussilago at once while the last developed ones will 

 hibernate; Lagerheim has made a similar observation (see Vgr. Micr. 

 rar. no 685). Lagerheim has observed (Vgr. 02 ^") that this species 

 like many others is able to propagate only by means of the uredo- 

 stage, and I have had it confirmed by seeing Puce, poarum st. II on 

 leaves of Poa alpina from the vast Breidamerkursandr (Iceland) many 

 miles from the nearest plant of Tussilago. St. I generally occurs in 

 May— August, st. II— III in July— October. 



Whither all cluster-cups on Petasites belong to this species has not 

 yet been proved (see Tranzschel 06); Bucholtz (05) and Schroeter 

 (89^^^) have found aecidia on Petasites, but they have made no cul- 

 tivating experiments. As far as I can judge a Puccinia found at Lyng- 

 by by M. L. Mortensen on Lolium multiflorum may not be classed 

 under any other species than the present one ; uredosp. 20—28 K^ diam., 

 teleutosp. 44—72 K X 25—28 K; all other features like Puce, poarum. 



Tussilago farfarus very common. Petasites alba. J. Blaakilde (^''/e 92 F. K. R.). 

 Poa annua, compressa, fertilis, nemoralis, pratensis, trivialis, common. 



1431. Puccinia agrostidis Plowright, Sydow 04'", Syn: Aecidium 

 aquilegiae Pers. 



Heter-eu-puccinia, st. I on Aquilegia, st. II— III on Agrostis alba &. 

 vulgaris. 



Aquilegia vulgaris. J. Hvidemose in Vendsyssel (June 04 M. L. M.). 



1432. Puccinia arrhenatheri (Kleb.) Eriksson, Sydow 04 '''^^ Syn: 

 Aecidium graveolens Shuttleworth, Draphavrerust (R 04 a ""). 



Heter-eu-puccinia with perennial st. I in Berberis, st. II— III in 

 Avena elatior. 



It is a curious thing that st. I which is so conspicuous because of 

 its producing witches-brooms on barberry has not been noticed in 

 Denmark until the last years (see R 02 a "') while st. II— III are so 

 common. 



Berberis vulgaris. J. Skive (F. K. R. Sept. 03 see R 04 b *"''), Hald near Vi- 

 borg!; F. Dalum (Jak. Lge see R 06 a'^); Lang. Tranekxr (Fabricius). Avena 



