. The British rust fungi (Uredinales) their biology and classification. Rust fungi. ON COMPOSITE 129 This genils occupies an intermediate position between Uromyces and the less advanced genera, Phragmidium, etc., as is shown by the fact that many species tend to form one-celled teleutospores (mesospores) indistinguishable from those of Uromyces, while others have spores with three or more cells, arranged as in Phragmidium, Triphragmium, Sphaerophrag- mium, etc. The number of species is enormous, more than 1300 are already known. The genus must therefore be subdivided, but no quite satisfactory
. The British rust fungi (Uredinales) their biology and classification. Rust fungi. ON COMPOSITE 129 This genils occupies an intermediate position between Uromyces and the less advanced genera, Phragmidium, etc., as is shown by the fact that many species tend to form one-celled teleutospores (mesospores) indistinguishable from those of Uromyces, while others have spores with three or more cells, arranged as in Phragmidium, Triphragmium, Sphaerophrag- mium, etc. The number of species is enormous, more than 1300 are already known. The genus must therefore be subdivided, but no quite satisfactory classification has as yet been discovered. Schroter's and Fischer's separate nearly allied species, while Arthur's is a pathless chaos. As a temporary measure, instead of adding a new imperfect scheme to those already existing, the species are here arranged on the plan adopted in Sydows' Monographia, in the order of the families and genera on which they art, parasitic; this has the advantage that it does, to a great extent, bring nearly allied species close together, while it is at the same time very convenient for ccnsultation. In each family the genera are arranged in the order familiar to British botanists, but the fami- lies themselves are in the order usually â adopted on the continent, because that will before loLg be accepted here also. 1. Puccinia Tripoli! Wallr. Puceinia Tripolii Wallr. Fl. Crypt. Germ. ii. 223. Cooke, Micr. Fung. p. 207; Gre- villea, iii. 180. P. Asteris Duby, Bot. Gall. ii. 888. Plowr. Grevillea, ii. 48 ; Ured. p. 215. Sacc. Syll. vii. 687 ' Sydow, Monogr. i. 15 p â_ Pig. 80. P. Tripolii. ^''^' Teleutospores (one Teleutospores. Sori amphigenous, con- abnormal). fluent into rather large, pulvinate masses, hard, compact, very dark-brown; spores oblong-clavate or clavate, rounded above or somewhat narrowed and much thickened (as much as 8/i), slightly constricted, generally attenuated downwards, G. Please note that these images are
Size: 981px × 2547px
Photo credit: © The Book Worm / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1910, bookpublishercambr, bookyear1913
