PHRAGMIDIUM 297 
7. Phragmidium Rubi Wint. 
Puccinia mucronata var. Rubi Pers. Disp. Meth. p. 38. 
Phragmidium Rubi Wint. Pilze, p. 230. Plowr. Ured. p. 224. Fischer, 
Ured. Schweiz, p. 418, f. 290. 
Monogr. iii. 141. 
Sace. Syll. vii. 745 p.p. Sydow, 
Spermogones. Epiphyllous, in minute clusters. 
Acidiospores. Caomata hypophyllous, roundish, or on the 
nerves elongated, often in little 
groups,surrounded byclavate para- 
physes; spores resembling those 
of P. molaceum. 
Uredospores. Sori hypophyl- 
lous, scattered; spores smaller 
than those of P. violaceum. 
Teleutospores. Sori small, on 
brownish spots, round, scattered, 
seldom more than 4mm. diam., 
black ; spores cylindrical, of 4—7 
(mostly six) cells, rounded above 
and mucronate with a colourless 
acute papilla (5—10 long), not 
constricted, rounded below, brown, 
beset with numerous little warts, 
70—115 x 2832, with three 
(or two) germ-pores to each cell; 
pedicels hyaline, as long as or 
longer than the spore, swollen at 
the base. 
Fig. 225. Ph. Rubi. Teleuto- 
spore x 360; uredospore x 600; 
a, teleutospore, boiled in lactic 
acid for one minute, x 600. On 
R. fruticosus. 
On Rubus fruticosus, R. caesius, R. saxatilis (?). Rather less 
common than P. violaceum. July—September. (Fig. 225.) 
Distinguished from P. violaceum by its smaller teleuto-sovi, and by the 
predominance of six-celled spores; the spots on the leaves are usually 
much less brilliant in colour. The form on Rubus saxatilis may be a 
distinct species, P. Rubi-saxatilis Liro, Ured. Fenn. 1908, p. 421; Sydow, 
Monogr. iii. 144, 
DisTRiBUTION : Europe. 
