154 



Puccinia Compositae. 



The sams author also records the fact that there are certain varieties of 

 chrysanthemum which do not take the rust, although growing among plani 

 badly rusted, but Jacky 3 tested a number of different varieties and found 

 them equally predisposed to the rust. 



Our chrysanthemum growers sometimes express a fear that the rust 

 on hollyhock, sunflower, and other plants may pass to the chrysanthemui 

 when it has suddenly bacome temporarily weak through drought or otht 

 causes ; but it ought to reassure them to know that the specific rust, known 

 ajs Puncinii chrysanthemi, is alone capable of producing infection on that 

 particular host. 



In the European material Jacky detected what he considers to be two- 

 celled uredospores, but Sydow regards them as two unicellular spores stuck 

 together. It miy be mentioned here to show the wonderful variety, that in 

 the Japanese material I found two uredospores borne on the same stalk, the 

 one slightly beneath the other. 



The teleutospore is sometimss described as smooth, but by careful focus- 

 sing it may be seen to be finely punctulated all over in the young stage, 

 although in the mature and deeply-coloured spore this is difficult to see, only 

 being visible on the thickened apex. 



The mesospores were obtained from the Japanese material, and are 

 rather rare. 



This rust was probably introduced into Europe from Japan, and it may 

 have reached Australia either from Europe or Japan. It is strange that th< 

 rust has not yet found its way into Victoria, considering the number 

 chrysanthemums imported from England, France, America, and Japan. 



It was first observed in England in 1895, although it probably exist 

 there before that time; in America in 1896 ; in France and Italy in 1897 

 and about 1898 it spread to Germany, then to Denmark and Switzerland, 

 and at length it has found its way to Australia. In 1904 it was 

 recorded for New Zealand by Kirk. 



It is found that many of the Australian-raised varieties are less liable 

 rust than others when grown in England or America. 



(Plate XXIX., Figs. 251-255 ; Plate E., Fig. 21.). 



Cichoriw 

 80. Puccinia cichorii (DC.) Bell. 



Bell., in Kickx. Fl. Fland. II. p. 65 (1867). 



Sydow, Mon. Ured. I., p. 49 (1902). 



Sacc. Syll. YIL, p. 606 (1888) ; XVII., p. 311 (1905). 



II. Uredosori amphigenous or on. stem, minute, pulverulent, scattered 



or confluent, girt or partially covered by ruptured epidermis, 

 cinnamon. 



Uredospores globose, subglobose or ellipsoid, echinulat 

 yellowish-brown, with one or two germ-pores on one face, sometin 

 three to four, 22-29 x 19-23 /i, or 22-25 /i diam. 



III. Teleutosori similar, dark-brown. 



Teleutospores intermixed sparingly with uredospores, ellij 

 or ovate-ellipsoid, brown to golden-brown, smooth, not or hard! 

 constricted at septum, apex rounded not thickened, base for 

 most part rounded or very slightly attenuated, epispore thii 

 germ-pore in each cell prominent, with finely granular contenl 

 27-38 X 19-25 ^, occasionally reaching 50 /* long, but averagii 

 35 x 20 p. ; pedicel hyaline, short. 



