312 THE JOURNAL OF BOTANY 



stages can be seen, and some of the spores assume almost the pedi- 

 cellate form of a paraphysis while still retaining the granular con- 

 tents of a spore. When the real spore first falls from its supporting- 

 cell, the base is evidently truncate, but afterwards it becomes 

 rounded off. 



The base of the proliferous stratum is a mass of hyphae similar to 

 those which can be seen in the intercellular spaces round the sorus. 

 The hyphae are rather coarse, colourless, much branched, septate, full 

 of oil-guttules, and about 5-0 /x wide. The peridium does not 

 extend underneath the spore-bed, and its cells do not present the 

 least appearance of being abortive spores like those of the secidiurn 

 of Puccinia. In fact, the two peridia must be held to be in no way 

 genetically related. The peridium of Milesina is a primitive and 

 imperfectly evolved protective covering formed from the mycelium, 

 while that of Puccinia Cctricis is a beautifully perfect shield' formed 

 by abortive spores which take on the function of protection in lieu of 

 reproduction. 



Ubedo anthoxanthina Bubak in Annal. Myool. 1905, iii. 223. 

 Kleb. u. Lind. in Flor. Mark Brand. Pilz. v a, p. 881. 



Uredosori numerous, on yellowish or faintly reddish spots of the 

 leaves, amphigenous but mostly epiphyllous, oval, about | mm. long, 

 pale rusty-brown, erumpent, soon naked and surrounded by the 

 upturned margin of the epidermis. Uredospores roundish or (mostly) 

 oval, 18-24 x 16-20 p ; contents, when fresh, oily and bright yellow ; 

 membrane almost colourless or pale yellowish, or even brownish, 

 l±li thick, echinulate (distance apart of the spines 1| li), germ- 

 pores indistinct: paraphyses very numerous, 60-70 /m long, "often 

 bent, thickened towards the apex with a capitate swelling, or often 

 two, one above the other, 12-19 /x wide ; membrane colourless or 

 faintly yellowish, 3-5 u thick, contents often yellow. 



On leaves of Anthoxanthum odoratum. Aberystwyth (Miss K. 

 Sampson) ; Ayrshire (Boyd) ; Worcestershire. May-July. Dr. 

 Wilson's Perthshire specimens may be the same. 



This species will doubtless be found to be common, if looked for 

 in the right places, which in my experience are rubbish-heaps by the 

 roadside, far from towns. The most remarkable fact about the sori 

 is that the paraphyses are extremely numerous, often more than 

 twice as many as the spores in the same sorus. No doubt this is the 

 uredo of "Puccinia authoxanthi" Plowr., but it is not P. an- 

 thoxanthi Fckl. After seeing the huge quantity and luxuriance of 

 growth of the paraphyses in the specimens noted above, it is impossible, 

 without overpowering evidence, to believe that the form without 

 paraphyses which has been found in Germany and Australia, and now 

 in Britain, can be the same. In all probability these are two distinct 

 species, but whether one of them is P. horealis Juel is very ques- 

 tionable. 



No teleutospores could be found. It seems possible that P. an- 

 tlioxunthi, as recorded by Plowright (p. 191), was formed by adding 

 the paraphyses which he observed to Fuckel's description' If &o, 

 "P. antkoxanthi" Plowr. has never existed. 



