432 BOTANICAL GAZETTE [November 



secondary infection from sporidia are localized in groups near the points of 

 infection. Neither the mvcelium nor the spores 



survive 



The teleutospores of this rust are of two kinds, and although they are 



indistinguishable 



typ 



of the second type produce slender germ tubes, whose terminal portions 

 break up into several independent cells or conidia. The sporidia put forth 

 germ tubes, which, penetrating the epidermis, make their way through the 

 epidermal cells either directly into the intercellular spaces or into the palisade 

 ceils, and thence into the intercellular spaces. New sori result from these 

 infections in 8-15 days. The conidia germinate, so to speak, by pouring 

 their content into the epidermal cells, from which it migrates into the palisade 

 cells, and finally through the entire plant. No outer visible sign results from 

 these infections. The protoplasm of the fungus enters into a state of sym- 

 biosis with that of the host, thus forming the mycoplasm. The seeds of such 

 infected plants produce seedlings in which the latent fungus manifests itself 

 by a general outbreak of sori over the entire plant when it is about three months 

 old. The change of the mycoplasm into mycelium is similar to that process 

 described by the author in former papers. 



Two other papers published shortly before the appearance of Eriksson's 

 account treat briefly of the mallow rust. In the first of these Taubenhaus 8 



germination 



> 



finds 



germ tubes produce sporidia like other promycelial cells. Furthermore, he 

 finds that the fungus is carried through the winter both by hibernating myce- 

 lium and by teleutospores. In plants in protected places, the mycelium 

 resulting from late infections appears to produce sori, which develop slowly 

 during the winter and mature the following spring. Regarding the hiberna- 

 tion of teleutospores, Taubenhaus finds that the teleutospores formed late 

 in the season seem to behave like those of a micro-Puccinia. Some of these 



found 



With 



time required for germinatio 



from 24 hours to 6 days. This observation is quite contrary to the experience 

 of Dietel, who found that the period required for the germination of the 

 teleutospores of Melampsora Larici Caprearum, a form with hibernating teleu- 

 tospores, decreased with the advance of the season. Young seedlings may be 

 infected by teleutospores borne in sori on the carpels and involucral bracts. 

 Thus the fungus is distributed by means of infected seed and pieces of involu- 

 cral bracts mixed with the seed, although the embryo is not infected. 



In the second paper Dandeno* gives brief additions to his formerly 



8 Taubenhaus, J. J., A contribution to our knowledge of the morphology and 

 life history of Puccinia Mahacearum Mont. Phytopathology 1:55-62. pis. 3- I 9 11 - 



» Dandexo, J. B., Further observations on the life history of Puccinia Mahace- 

 arum. Rep. Mich. Acad. Sci. 12:91, 92. 1910. 



