May 1907] Uredinales of North American Flora 98 



The fifth genus, Melampsoridium, estabHshed by Klebahn, 

 1899, includes one species, M. betulae (Schum.) Arthur — the 

 aecia on Larix not yet found in America, the uredinia and teha 

 on Betula, widely distributed. The sixth genus also includes 

 but one species — Melampsorella elatina (Alb. & Schw.) Arthur, 

 the aecia on Abies and the I and II forms on Alsine and Ce- 

 rastium. The seventh genus has this representation : Hyalopsora 

 aspidotus (Peck) Magn., Hyalopsora polypodii (DC.) Magn., 

 Hyalopsora laeviuscula (Diet. & Holw.) Arthur, and Hyalopsora 

 cheilanthis (Peck) Arthur; the hosts for these all being plantae 

 polypodiaeceae. The next occurs on Vaccinium (the aecia on 

 Abies not recorded for America), namely Calyptospora colum- 

 naris (Alb. & Schw.) Kuehn. Then we haye a new genus, 

 Necium, with the single species, N. farlowii Arthur n. sp. on 

 Tsuga canadensis (L.) Carr. The tenth genus is exclusively 

 filicicolous, Uredinopsis, founded by Magnus in 1893. The 

 American species are U. osmunda Magn., U. mirabilis (Peck) 

 Magn., U. pteridis Diet. & Holw., U. copelandi Syd., U. struthi- 

 opteridis Stroemer, and U. phegopteridis Arthur n. sp. 



The last two subfamilies of the Order Uredinaceae are Chryso- 

 myxatae, with the cingle genus Melampsoropsis ; and Cronar- 

 tiatae, with the genera Cronartium, Cerotelium, Cionothrix, Al- 

 veolaria, Baeodromus, Endophyllum. and Pucciniosira. In both 

 these subfamilies the pycnia and other sori originate beneath the 

 epidermis, and the teliospores are catenulate. In Chysomyxatae 

 the aecia (if present) rupture their periderm apically ; in Cro~ 

 nartiatae, when present their inflated periderm has circumscissile 

 dehiscence. The urediniospores in the first are catenulate; in 

 the second they are borne singly on pedicles. 



We content ourselves with a mere enumeration of the spe- 

 cies of the two subfamilies just outlined, most of which will be at 

 once recognized by mycologists: Melampsoropsis empetri (Pers.) 

 Arth.; M. pyrolae (DC.) Arth. ; M. ledicola (Peck) Arth. ; M. 

 cassandrae (Peck & Clinton) Arth.; M. abietina (Alb. & Schw.) 

 Arthur; M. arctostaphyli (Dietel) Arth. ; M. piperiana Arthur 

 n. sp. ; M. chiogenis (Dietel) Arth.; Cronartium comptoniae 

 Arth.; Cr. comandrae Peck. ; Cr. quercus (Brondeau) Schroet. ; 

 Cr. ribicola Fisch. de Waldh. ; Cr. coleospoirides (Diet. & Holw.) 

 Arthur; Cerotelia canavaliae Arth.; Cionothrix Arthur n. gen. 

 and C. praelonga (Wint.) Arthur; Alveolaria cordiae Lagerh. ; 

 Baeodromus eupatorii Arthur ; B. holwayi Arth. ; B. californicus 

 Arth; Endophyllum rivinae (B. & C.) Arthur; End. vernoniae 

 Arthur; Pucciniosira pallida (Speg.) Lagerh.; and P. brickelliae 

 Diet, and Holw. 



An analysis of the Aecidiaceae will be reserved until the 

 next part of the North American Flora appears with the con- 

 clusion of that family. 



Here it may be remarked that the large page, clear type, 



