164 NORTH AMERICAN FLORA [V01.UMB 7 



16. PHRAGMIDIUM Unk, Ges. Nat. Freunde Berlin 



Mag. 7: 30. 1815. 



Puccinia P.ers. Neues Mag. Bot. 1 : 118. 1794. Not Puccinia Willd. 1787. 



Caeoma Link, Ges. Nat. Freunde Berlin Mag. 3 : 5, in part. 1809. 



Hypodermium Link, Ges. Nat. Freunde Berlin Mag. 7 : 26. 1815. Not Hypoderma DC. 1805. 



Aregma Fries, Obs. Myc. 1 : 225. 1815. 



Epitea Fries, Syst. Myc. 3 : 510. 1832. 



Lecythea L€v. Ann. Sci. Nat. HI. 8 : 373. 1847. 



Cycle of development includes pycnia, aecia, uredinia, and telia, with indistinct alter- 

 nating phases ; autoecious. Pycnia subcuticular, other sori subepidermal. 



Pycnia conoidal, or flattened and indefinite, often extending downward between the 

 epidermal cells ; hymenium flat ; ostiolar filaments wanting. 



Aecia erumpent, mostly indefinite, without peridium, but usually encircled by paraph- 

 yses. Aeciospores catenulate, globoid ; wall nearly or quite colorless, finely verrucose. 



Uredinia erumpent, definite, usually encircled by paraphyses. Urediniospores borne 

 singly on pedicels, often with paraphyses intermixed, globoid or ellipsoid ; wall nearly or 

 quite colorless, verrucosely or echinulately sculptured, the pores several, scattered, indis- 

 tinct. 



Telia erumpent, often first arising from the uredinia, usually definite, without 

 paraphyses. Teliospores two- to several -eel led by transverse septa ; wall somewhat lami- 

 nate, colored, more or less coarsely verrucose or even smooth, hygroscopic layer obscure, 

 the pores two or more in each cell and lateral ; pedicels refractive and usually more or 

 less hygroscopic in lower part. 



Type species, Puccinia mucronata Pers. (on Rosa centifolid). 



Host belonging to tribe Rubeae (family Rosaceae) . 



Uredinial paraphyses cylindrical or somewhat clavate, the wall not or only slightly thicker above. 

 Urediniospore-wall thin ; teliospores broad (32-35,"), 4-6-celled. 1. P. Peckianum. 

 Urediniospore-wall moderately thin ; teliospores rather slender 



(26-30 /i), 6-10-celled. 2. P. imitans. 



Uredinial paraphyses distinctly clavate, the wall much thicker above. 

 Urediniospore-wall thin ; teliospores rather broad (29-34 ,u), 7-10- 



celled. 

 Urediniospore-wall moderately thin ; teliospores rather slender 



(26-29/^), 6-9-celled. 4. P. occidentale. 



Host belonging to tribe Roseae (family Rosaceae). 



Urediniospore-wall thin, about 1/^ ; teliospores slender, 8-11- (mostly 



9- or 10-) celled. 

 Urediniospores 18-20," and teliospores 65-100 /i long. 5. P. americanum. 



Urediniospores 20-26^ and teliospores 85-125," long. 6. P. Rosae-setigerae . 



Urediniospore-wall moderately thick, 1.5-2 /i. 

 Teliospores slender, 7-11- (mostly 9-) celled. 

 Upper part of teliospore acute. 



Pedicel much longer than the spore, swelling slightly. 7. P. Rosae-acicularis . 



Pedicel about the length of the spore, swelling greatly. 8. P. montivagum. 



Upper part of teliospore acuminate ; pedicel much longer than 



the spore. 

 Teliospores stout, 5-8- (mostly 6- or 7-) celled ; pedicel longer than 



the spore. 

 Teliospores blackish, the upper part acute. 



Swollen part of pedicel about as long as its upper part. 10. P. Rosae-arkansanae . 



Swollen part of pedicel much longer than its upper part. 11. P. dtscifiorum. 

 Teliospores brown, the upper part acuminate. 12. P. subcorttcinum . 



Host belonging to tribe Poieniilleae (family Rosaceae), 



Teliospores apiculate ; pedicels much swollen in lower part. ^ ^ „ ^ ^ 



Teliospores 3-5- (mostly 4-) celled ; apiculus small. 13. P. Andersom. 



Teliospores 4-10- (mostly 5-8-) celled; apiculus large. _ 14. P.Jonesii. 



Teliospores not apiculate ; pedicels not or only slightly swollen m 



lower part. . , , , i =- n r • 



Teliospores 2-4- (mostly 3-) celled ; pedicels short. 15. P ^^^f^^f- 



Teliospores 3-5- (mostly 4-) celled; pedicels long. 16. P, PotenHllae. 



1. Phragmidium Peckianum Arthur. 



Lecythea speciosa Peck, Bot. Gaz. 3 : 34. 1878. Not Phragmidium speciosum Cooke, 1875. 

 Uredo speciosa De-Toni, in Sacc. Syll. Fung. 7 : 860. 1888. 



O. Pycnia epiphyllous, few, gregarious, in small groups on discolored spots, incon- 

 spicuous, subcuticular, pale honey-yellow, discoidal, low, 128-160 /^ broad, 32-38 /^ high, 



often confluent. 



3. p. Ruhi-odorati . 



9. P. Ro sae -calif ornicae . 



