00 



UROMY< ES 



U. Pm Winter, Krypt Flor. i. L63. Cooke, Grevillea, vii. L35. Plowr. 

 [Jred. p. 133. Sacc. S\]]. vii. 542 p.p. Sydow, Monogr. ii. L24. 

 Fischer, [Jred. Schweiz, p. 28, f. 22. 



Spermogones. Hypophyllous, numerous, scattered amongsl 



the a-cidia. 



/Ecidiospores. ^Ecidia distributed uniformly over the lower 

 surface of the leaf, cup-shaped, with ;i while, torn, broadly 

 revolute margin; spores densely and minutely verruculose, 



orange, 18 — 23 /x. 



i r rcf/')sj)nre.s. Sori generally hypophyllous, scattered, minute, 

 soon naked, pulverulent, cinnamon; spores 

 globose or subglobose, minutely verruculose, 

 yellow-brown, 21 — 25 fi diam. ; epispore 1^ — 

 2h /j. thick, with 3 — 5 germ-pores. 



Teleutospores. Sori similar, but sometimes 

 confluent and larger, dark-brown; spores sub- 

 globose to ovate, with a small hyaline papilla 

 (as much as 3 p. high), everywhere minutely 

 and rather densely verruculose, brown, 20 — 

 2^1x14 — 22 yu,: epispore 1£ p, thick ; pedicels 

 hyaline, short, deciduous. 



.Ecidia on Euphorbia Cyparissias, May, June; uredo- and 

 teleutospores on Pisum sativum and Lathyrus pratensis, July — 

 September. Rare. (Fig. 54.) 



Although both will equally infect E. Cypurissias, it is probable that 

 the Uromyces on Pisum is biologically distinct from that on Lathyrus. It 

 is not certain that the latter has been found in this country, but the 

 former is recorded from various places. It must be remembered that 

 U. Fabae occurs also on the same two genera, though all the spore-forms 

 of the two can be easily distinguished. 



An secidium on /:'. Cyparissias, and attributed to U. Pisi, was found 

 at Dover, May, 1909 (Rev. T. Taylor) ; the specimen is in the British 

 Museum, but there is no proof that this belonged to U. Pisi, because it 

 has been shown that U. Loti, U. striatus (both of which are British), as 

 well as two other (non-British) species, equally produce on E. Cyparissias 

 secidia which are morphologically indistinguishable. This secidium pos- 

 sesses a perennial mycelium, which permeates the whole host and deforms 

 and bleaches it. The connection of one form of it with Uromyces Pisi 

 has been experimentally demonstrated by Schroter, Rostrup, Fischer and 

 others. The Uromyces on Vicia Oracca which was formerly considered to 



FiK. 54. U. Pisi. 

 a, a cidia and s, 

 spermogones on 

 leaf of Euphor- 

 bia ( 'yparissias 

 (from the Dover 

 specimen). 



