IC , Uromycladutm. 



Dietel observes that the occurrence of bicellular teleutospores is rare 

 amoiiL' r/v,wyr/-x, for only once has he observed it in U. pisi and U. junci, 

 and two were found in U.'limosel/ae. Dr. Cooke has also found a few in 

 U. trifolii, and I have now to add U. orchidearum, U. tricorynes, U. vesi- 

 culosus and U. politus. 



Darlucafilum Cast., is generally very plentiful on uredosori. 



(Plate XVIII., Fig. 155-157 ; Plate G., Fig. 33.) 



UROMYCLADIUM McAlp. 



This new genus of Busts is noteworthy, not only on account of the 

 teleutospores forming a cluster at the top of the stalk, and generally accom- 

 panied by a colorless cyst, but from the large galls produced by some species 

 which seriously disfigure and ultimately destroy many of our Wattle-trees 

 (Acacias). 



The seven species at present known show every gradation from one teleu- 

 tospore accompanied by a cyst (U. simplex) through two teleutospores with 

 or without a cyst (U. maritimum), (U. bisporum), and reaching to three teleu- 

 tospores in a head always without a cyst (U. tepperianum). The presence 

 of more than one teleutospore at the end of a stalk is a novel feature in 

 rusts, and the addition of a colorless vesicle or cyst at the base reminds one 

 of Ravenelia to which this genus is allied. The unicellular teleutospore also 

 links it on to Uromyces, and I consider that here we have the connecting 

 link between Uromyces on the one hand and Ravenelia on the other. The 

 genus Anthomyces with only a single species is composed of a head of three 

 or more cells united together with sterile cells at the base, and may prove a 

 bridging species from Uromycladium to Ravenelia. Spermogonia, uredo 

 and teleuto sori occur, but no aecidia. The two gall-producing species 

 hitherto found are U. notabile and U. tepperianum, both of which produce 

 three teleutospores at the top of the stalk, and the former has uredospores 

 in addition. The only species known outside of Australia is that of U. tep- 

 r rianum (formerly called Uromyces tepperianus, Sacc.), and it is noted for 

 causing deformation of the shoots, but with us it is ruining whole plantations 

 of Wattles. Near Altona Bay, Victoria, the branches of the beautiful 

 Golden Wattle (Acacia pycnantha) are deformed and destroyed by it when 

 it forms numerous galls sometimes as large as a potato. In the neighbour- 

 hood of Melbourne, too, hedges of the Kangaroo thorn (A. armata) are 

 l>eing gradually and completely destroyed by this fungus. Some of the 

 shrubs have most of their branches infested with the chocolate colored 

 galls, the color being due to the spores, and they may be in the form of a 

 succession of small ones as large as peas, or large ones the ssize of walnuts. 

 The phyllodes as well as the branches in some species are deformed. On 

 cutting across these galls they are seen to be solid to the core, and 

 not the product of insects but of the fungus, although in many cases bored 

 and tunnelled by insects after being produced. When our Acacias are 

 more closely examined for rusts no doubt the number of species will be con- 

 siderably increased. 



General characters Spermogonia somewhat hemispherical, produced under 

 the cuticle, without paraphyses at mouth, preceding the formation of any 

 other spore. 



Uredospores solitary at apex of basidia, and generally much larger than 

 teleutospores with several distinct germ-pores. 



Teleutospores in clusters, composed of one spore and cyst or two or more 

 spores with or without a cyst, depressed globose. 



