W. MCRAE 255 



water-cultures those of P. Meadii are smaller than those of P. Faberi, the limits 

 of P. Faheri growu on Hevea fruits come fairly close to those uf P. Meadii in 

 water- culture. 



P. Faheri sporangia . . 34 — 70 x 16 — 36/it on cacao fruits. 



32 — 66 X 25 — 32/^1 in water-culture. 



32 — 44 X 20 — 32/it on Hevea fruits. 



P. Meadii sporangia . . 33 — 67 x 14 — 28/x on Hevea fruits. 



20 — 44 X 16 — 29/A in water-culture. 



The spjrangium of P. Faheri is usually slightly nearer the spherical shape 

 than that of P. Meadii. The papilla of P. Faheri is, as a rule, more protuberant 

 than that of P. Meadii, and the base of the sporangium of the former has a cellulose 

 plug nmch more frequently than has the latter. The zoospores are very nearly 

 alike. Those of P. Faheri measure from 8— 12"8/x on cacao fruits, while they 

 measure 8 — -lO/x on inoculated Hevea fruits, those of P. Meadii measure 7 — -lO-D/^. 

 The number of zoospores is nearly alike, in P. Faheri being 16 — 24 and in 

 P. Meadii 14—22 under similar conditions. Though in a few instances numbers 

 up to 40 have been counted in P. Meadii this difference is rather discounted 

 perhaps by the fact that a larger number of those of P. Meadii have 

 been counted and under more varied conditions. Resides Rorer^ records 

 the number as 15 to 30. In my material and cultures of P. Faheri I 

 found resting conidia only, and they were produced in abundance on cacau 

 fruits, inoculated Hevea fruits and in culture. Tbey were light yellow 

 in colour with a smooth wall about 2^ in thickness and varied from 

 28 — 46 X 26 — 43/>t. Coleman,^ however, found oogonia and oospores, and 

 figs. 4 — 6 in Plate XVIII of bis paper show the " oogonial wall for the 

 most part closely applied to that of the oospore." He remarks, *' In some 

 examples, from the mode of attachment of the oogonial stalk, it appears as if 

 the oogonial wall had become directly the wall of the oospore by a process of 

 thickening. This was in all probability not the case, as the oospore almost 

 always fills the oogonial cavity so completely that the oogonial wall can be 

 made out only with difficulty." Coleman seems to have had genuine oogonia 

 in some at least of his preparations. Rorer^ also figures an oogonium in 

 Plate XVII, fig. 14 of his paper, and in it the oospore occupies the great part of 

 the oogonium. In P. Meadii on the other hand, the wall of the oogonium is 

 easily distinguishable from that of the oospore and when mature the oospore 



^ Rorer, J. B. " Pod-Rot, Canker, and Chupon-Wilt of Cacao caused by Ffii/tophtkora sp." 

 Bull. Dept. of Agric, Trinidad, IX, No. 65, pp. 79—120, 1910. 



* Coleman, L. C. " Disoasea of the Areca Palm." Dept. of Agric, Mysore State, Mijcological 

 Series, Bull. 2, 1910, also Ann. Myc, VIII, pp. 591— G2G, 1910. 



