143 
ON THE BIOLOGY 
OF A 
NAMATELIA Fr. 
By H. MARSHALL WARD, Sc. D. F.RS., &e. 
During some investigations on the Hymenomycetes which grow on 
Pine-leaves made last Autumn, I found on the isolation-plates a yeast- 
like form the behaviour of which puzzled me exceedingly. 
It grows readily on wort-gelatine, showing up in two days as circular 
plates of a pale yellow colour which soon spread, until in ten days toa 
fortnight each forms a slightly raised disc an inch or more in diameter, 
honey-yellow and marked with radiating vein-like ridges of a deeper 
orange or brick red colour, all spreading like wrinkles from a central 
spot of the same hue (Fig. 1). I have had such discs nearly 24 inches in 
diameter on the plates. Careful examination shows that these discoid 
growths are very glairy or gelatinous compact masses of mycelia, but in 
old cultures, when they dry up, they become exceedingly brittle and 
almost like horn. Immersed in the mass are two kinds of bodies, 
yeast-cells and what I shall term. chlamydospores. Examination of 
the pale yellow young colonies, about the second day, shows that each 
consists of actively budding yeast-cells (Fig. 4) radiating from a 
common centre and forming a pasty mass which slightly softens or 
liquefies the gelatine. This mass is fringed by a number of short 
hyphe radiating at the margins like a fringe of cilia. (Figs. 4, 6, 8 
and 13). On the third day these radiating hyphe have increased in 
number, as have also the yeast-cells from which they radiate, and here 
and there the hyphe show swellings along their course. (Fig. 2). 
Each swelling is ovoid and soon fills with oily looking drops, and be- 
comes segmented off from the rest of the hypha by a septum at each 
end, or, when terminal, below only. 
As the colony grows, the central core of yeast-cells increases, and 
the number of radiating hyphe and their swellings augment (Figs. 8 
and g), and the older, wrinkled discoid colonies (Fig. 1) consist of 
many hundreds or thousands of the latter radiating out from countless 
yeast-cells. The older more central oval bodies have by this time ob- 
tained thicker well-defined walls and are crammed with oil-drops, and 
are evidently of the nature of chlamydospores (Fig. 3), and will be 
termed so in what follows. 
Obviously the first step was to determine beyond doubt that the 
