Uromycladium Leguminosae. 107 



Acacia. 

 29. Uromycladium maritimum McAlp. 



O. Spermogonia at first ruddy-brown, ultimately black, dotted over the 

 surface of prominent discoid tubercles, formed at corresponding 

 points on both surfaces of the phyllodes, somewhat hemispherical, 

 but broader than deep, and produced beneath the cuticle, 

 averaging 120 ^ diam. 



Spermatia hyaline, shortly ellipsoid, 3 x 2 p. 



II., III. Sori dark-brown, elongated, compact, confluent, rupturing 

 epidermis, 2-3 mm. long, partially surrounding the black discoid 

 spermogonial tubercles. 



II. Uredospores oval to elliptical or elongated elliptical, pale-brown to 



dark-brown, warted all over and thickened at apex, where spikes 

 are specially prominent, forming a tuft, with very distinct 

 equatorial pores, 3-7 on one face, very variable in length and 

 breadth, 45-60 x 24-28 ju ; pedicel deciduous, hyaline, elongated, 

 up to 106 x 5 ju. 



III. Teleutospores at first intermixed with uredospores, two on each 

 sporophore, with a lower and lateral colorless vesicle, very rarely 

 three spores in cluster without a vesicle, subglobose to de- 

 pressed globose, dark-brown, thick walled, smooth, with finely 

 granular contents, slightly thicker at apex, with very prominent 

 apical germ-pore, 30-32 ^ diam., or 22-25 x 24-30 ju ; colorless 

 vesicle globose, with very thin wall, and arising from stalk 

 immediately beneath septum, 30-35 ju diam. 



X. Mesospores intermixed with the uredospores, or even with uredospores 

 and teleutospores, unicellular or very rarely bicellular, pale, 

 smooth, with wall of equal thickness and finely granular contents, 

 without any visible germ-pores, fusiform or ellipsoid, or even 

 occasionally clavate, solitary at the end of a stalk like the 

 uredospores, 22-45 x 11-19 /*, occasionally up to 57 JJL long. 

 On phyllodes and stems of Acacia longifolia Willd. 

 Victoria Saudringham and Beaumaris. 

 Tasmania Mersey Bluff, Jan., 1906 (Robinson). 



II. April to August, occurring alone, or sparingly mixed with teleuto- 

 spores. III. September to latter part of spring and during summer, 

 intermixed with a few uredospores. 



In one form or another it occurs all the year round. 



This rust was first found on the coast at Beaumaris in 1895 on Acacia 

 longifolia, although not investigated at the time, and it was in this species 

 that the peculiar grouping of the teleutospores and the presence of a 

 colourless vesicle or cyst was first observed. 



The teleutospores germinate freely in water or moist air and without a 

 period of rest. They germinate all round the sorus on the surface of the 

 phyllodes, forming a flaky mass of spores and sporidiola, which easily peels off. 

 The uredospores were only found to germinate in water in the spring. 

 The spermogonia are associated with uredo and teleutospores occurring 

 in the same sorus. 



Only in rare instances were sori found without being accompanied by 

 spermogonial tubercles. 



(Plates XX., XXL, Figs. 166-184; XXIV., Figs. 216, 217; XXXII., 

 Fig. 273; XLIIL, Figs. 313, 314, 315.) 



