366 A. Barclay — List of the Uredinese occurring [No. 3, 



The germination of these secidiospores is very peculiar and un- 

 like that of any other species with which I am acquainted, with 

 the single exception of the aecidiospores of the -^cidium on another 

 Euphorbiaceous plant (Andrachne cordifolia) described fui'ther on. I 

 have not here, unfortunately, access to special memoirs on the develop- 

 ment of individual Uredines, so that I am unable to state definitely that 

 the mode of germination of these spores is altogether unknown, but, so 

 far as I have been able to consult the works of others on this subject, I 

 have not seen this mode described. The spores germinate fairly readily 

 in water, throwing out the usual single germ-tube, measuring 5 ft in 

 diameter (Fig, 7, PL XY.). After a time, from 24 to 48 hours, a secon- 

 dary spore (sporidium ?) is formed at the end of the germ-tube, not 

 upon any sterigma, but simply separated from the tube by a septum 

 (Fig. 9, PL XV.). This secondary spore is round or oval, is double- 

 contoured, and contains well defined granules in a mass of proto- 

 plasm (Fig. 9, PL XY.). They measure as a rule 14 /a in diameter. The 

 day after the formation of this secondary spore, it germinates while 

 still attached to the primary germ-tube, throwing out a secondary 

 germ-tube which soon takes on a spiral form (Fig. 8, PL XY.). After 

 this, the whole structui^e perishes, and I have not been able to deter- 

 mine its future history. 



Remarks. — This ^cidium is evidently not JEc. jEupJiorhioe, Grmelin, 

 (or TJromyces Pisi, Pers.), as in this species the mycelium is described 

 as pervading the whole plant or shoot, deforming all the leaves and 

 preventing the formation of flowers on the shoots attacked. In the 

 ^cidium above described, only local and well-defined areas of the leaves 

 are attacked by the mycelium ; the leaves are not altered in general 

 shape, and the shoots bear flowers as usual. For much the same 

 reasons this ^cidium is not TIromyces scutellatus, Lev., which also 

 markedly deforms the leaves. It remains to consider its affinities with 

 the genus Bndophyllum and especially with E. EupJiorhice silvaticce, 

 D. C, on Eupli07'hia amygdaloides, which is said to cause a well defined 

 alteration in the leaves of the host, rendering them shorter and wider 

 and somewhat fleshy, and discolouring them to a pale yellowish green 

 colour. Moreover, this parasite has orange-yellow spores 16 to 26 /* 

 long and 12 to 18 /a wide, whilst in the Simla ^cidium the spores are 

 colourless or pale brownish and measure, as stated above, 22 x 20 ft to 

 19 X 18 ft. Moreover, the germination of the secidiospores of the last 

 mentioned ^cidium is difl^erent from that described in the case of 

 Endophyllum, which is essentially of the nature of the germination of 

 teleutospores. There is, however, some resemblance between the two 

 ^cidia in this respect, for we may consider the secondary spore of the 



