330 
W. B. Mercer, 
It would seem, therefore, that the secondary fruit form of the Phojna 
represents a new species of Alternaria. 
11. Principal Results. 
1. A fungus which cannot be identified with any species previously des¬ 
cribed, and to which it is proposed the name of Phoma Richardiae 
should be given, was found on decaying leaves of Richardia africana. 
It is not parasitic on the latter plant. 
2. The fungus has two conidial forms, and produces mycelial gemmae. 
It may be described as follows: 
Mycelium at first hyaline and colourless, with numerous oil drops; 
yellow-brown with age. 
Pycnidia round or oval 120—150 ju in diameter, at first yellow, 
darkening with age to brown-black; with a short, usually 
tapering neck 20—30 ju in diameter, darker than the body in 
early life. Cavity very densely packed with spores. Wall of 
two or three layers of irregular, undifferentiated cells. An 
extremely variable organ ; on artificial media often very irregular 
in shape, with no neck, and varying between 20 and over 
200 /J, in diameter. 
Pycnospores unicellular, hyaline, oval or egg shaped, with two 
or three oil drops towards either end, 6—7 /jl long and 4 ju 
broad; borne directly on the innermost wall cells, with no 
sterigmata; extruded in masses. 
Free conidia borne in simple or branched chains on unbranched 
conidiophores, 5—50 ju long, or at the end of long branches. 
Spores pear-shaped, oval, or irregular, brown-black, thick 
walled, smooth, with three or four cross walls, and sometimes 
one or two longitudinal or oblique, 20—40 /a long and 15 to 
25 fi broad. „Zwischenstück“ up to 30 ju long. 
A species of Alternaria, not identifiable with any pre¬ 
viously desbribed. 
Gemmae developed on mycelium, in old cultures, dark coloured, 
thick walled, very variable in shape; of three types: 
a) Special branches resembling distorted brown conidia or 
chains of conidia, 
b) Local stretches of hyphae, 2 — 10 cells in length, 
c) Grape-like masses of cells, intercalary or terminal. 
3. The pycnidia are evolved in two distinct ways: 
a) Symphyogen. Hyphae weave together and branch profusely, 
forming a dense cellular mass or primordium. A cavity, in which 
the spores are formed, arises in the centre, while the mass is 
still growing in bulk, and expands with the mass. 
b) Meristogen. The primordium is formed by the repeated division 
of a few adjoining cells of a hypha, usually aided by the fusion 
of short branches. 
Under certain circumstances the pycnospores may divide in 
this manner to form pycnidia direct. 
Many intermediate methods of formation occur, a more or less regular 
sequence from one extreme to the other being observed in some 
cultures. 
