117
118
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W. R. IVIMey Cook,
and Anbury; in the United States as Club Root; in France as hernie; in Italy as ernia; in Germany as Kropfkrankheit; in Holland as Knolvææet and in Denmark as Kaalbrok. The life history has already been described as the type in this paper and is illustrated in Text figure 1.
2. P. Fici-repentis Andreucci.
Andreucci, A. Archivio Botanico. Vol. 2. Pp. 18-28. 1926.
Spores spherical, 1.5 in diameter, with thin smooth hyaline mem- branes. Free, not joined in groups. Spores on germination give rise to swarm spores 2.7 long with a flagelhim equal in length to the swarm spore. Swarm spores develop into amaba and these into plasmodia. Plasmodia aggregate to form macrocysts which subsequently produce fresh plasmodia. Plasmodia finally produce spores.
The organism causes hypertrophy of the roots of Ficus repens, the galls being up to 5 cms, in diameter. Once recorded from a garden in Siena, Italy.
I have not been able to examine slides of this species and this des- cription is based upon the original description. Material of this species. which is in my possession is too dry to allow sections to be obtained which will confirm the work referred to.
P. Diplantherae (Ferdinandsen & Winge), Cook nov, comb. (Pl. 13, fig. 2)., Syn. Ostenfeldiella diplanthera Ferdinandsen C. & Winge O. Ann. Bot. Vol. 28. Pp. 643-
649. 1914.
Spores spherical 4 in diameter with smooth yellow walls. Spores not enclosed in a common membrane, nor arranged in a definite system. Plasmodia produced from the spores very large 125μ-200μ in diameter and completely filling the host cells. The organism causes hypertrophy of the host, attaking the stem. Found on Diplanthera Wrightii, on the island of St. Croix, in Danish West Indies, and recorded from material preserved in alcohol only.
Owing to the conditions under which the material was preserved only a rough general examination was possible and very little is known regarding the life-history up to the production of spores.
Genus 2. Sorosphaera. Schröter. (Pl. 14, fig. 1).
Schröter, J. Cohn's Kryptogamenflora von Schlesien. Vol. 3. Pp. 1-
500. 1886-1897.
Spores arranged in hollow spore-balls, spherical or ellipsoidal in shape. Individual spores ellipsoidal or pyriform and the whole spore-ball enclosed in a common membrane, one spore-ball being produced from each plasmodium. Spores on germination give rise to swarm spores, which fuse in pairs, producing fresh plasmodia. Infection occurs chiefly through root hairs. The species cause some hypertrophy to the host tissue, though only when the fungus enters the cortical tissue is is well marked.
The Hong Kong Naturalist.
The Hong Kong Naturalist Supplement.
No. 1.
Plate 15, figure 1.
Sorodiscus Callitrichis, Spores x 320.
Plate 15, figure 2.
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Sorodiscus radicicolus, Spores x 320.