D. Keilin 89 
Family Saccharomycetaceae. Monocellular, sporogenic budding fungi. 
Each cell is a potential sporogenic cell (or ascus). The number of spores & in 
the ascus is usually 1 to 4, seldom 12. The spores are monocellular. Typical 
mycelium is formed by a few species. 
A. Spore rounded, oval, pileate or lemon-shaped with or without pro¬ 
jecting rim. 
I. Group. In Saccharine nutrient liquids they furnish only sedimental 
yeast at the outset, surface films occur only at a later period, if at all. Films 
more or less mucilaginous. Spore smooth, globular or oval, with 1 or 2 mem¬ 
branes. Spore germinates either by gemmation or by producing a promycelium. 
Great majority produce alcoholic fermentation. 
Genus 1. Saccharomyces Meyen. Spore with single membrane; germinates 
by ordinary gemmation. In addition to yeast cells a few of them produce 
mycelium with well defined septa. 
Genus 2. Zygosaccharomyces Barker. Ascus is formed after cell fusion. 
Genus 3. Saccharomycodes Hansen. Spore with a single membrane, 
germinates into a promycelium, the new cells, being incompletely separated, 
form a mycelium with well defined septa. 
Genus 4. Saccharomycopsis Schionning. Spores with two membranes. 
II. Group. Film produced on the surface of nutrient solution immediately 
after the same has been inoculated. The film has a dry dull appearance due 
to the inclusion of air bubbles. Several species produce esters, and a few of 
i them do not cause fermentation. Spore with a single membrane, of different 
shapes with or without projecting edge. 
Genus 5. Pichia Hansen. Spore rounded, hemispherical or irregular and 
J angular. A strong mycelium is formed. No fermentation. 
j . Genus 6. If illia Hansen. Spore pileate, or lemon-shaped, with a projecting 
nm. Most of the species possess considerable ester-forming powers, but a 
few do not produce fermentation. 
. B. Spores acicular or spindle-shaped, parasitic fungi. 
Genus 7. Nematospora Peglion. Elongated budding cells; sausage-like 
| ascus containing eight unicellular spores in two bundles of four. & Spore 
. t ^ 1^ & & lum, which is lost before germina- 
tion Parasitic on hazel-nuts in Italy. Grows well on sugar-beet or meat- 
broth gelatin, badly in liquids where it forms mycelium only. One species- 
N. coryli Peglion (Fig. III). 
Genus 8. Monosporella (= Monospora Metschnikoff 1884) Buddin- 
yeast-like fungi, each cell a potential ascus. The latter is elongated and 
