444 THE MONILLE AND OIDIA. 



impossible to speak of fructification at all ; and even in the few 

 species, like Manilla sitophila, which throw up hyphae resembling 

 conidiophores, the difference between vegetative cells and repro- 

 duction cells is very slight and confined entirely to the shape. 

 Thus, in Monilia sitophila, both the conidia and the mycelial cells 

 are of a uniform orange-yellow colour. In some species, e.g., 

 Monilia variabilis, the tubular or Oidium cells occasionally dis- 

 play unevenly distributed tubercles or points, on which the yeast- 

 like conidia are sessile, and which might be regarded as sterig- 

 mata ; but this is all. Hence, in Monilia, we have merely to deal 

 with vegetative yeast conidia (see p. 21, vol. ii.), which do not 

 differ materially from the cells of the bud mycelium either in 

 shape, contents or origin. 



A comparison of the budding cells of a Saccharomyces and a 

 Monilia easily reveals a remarkable difference in the appearance 

 of the protoplasmal contents. In Monilia these are more 

 delicate, homogeneous, so that the cell is lighter in appearance, 

 and the large vacuoles, invariably present, contain a spheroidal 

 granule that is in constant rapid motion. According to A. 

 GUILLIERMOND (VI.), these bodies are identical with Babes' 

 metachromatic granules or Butschli's red granules, and are 

 similar to the chromatin granules in bacteria. Hansen and 

 Guilliermond state that a cell nucleus is present; but, as in most 

 cells, it is not visible. 



Monilia Candida (Bonorden), Hansen, affords the finest 

 examples of the typical forms of growth. E. 0. HANSEN (XLVI.) 

 investigated this fungus, and identified it with a species described 

 by BONORDEN (I.). The morphological variations of this species 

 are highly diversified. When grown on sweet fruits or fresh 

 cowdung, it appears as delicate mycelial filaments, whereas in 

 saccharine liquids and on solid media a yeast like growth pre- 

 dominates (see Fig. 99). This latter form is seen at its best in 

 hopped beer wort, where the globular to ellipsoidal cells produce 

 buds actively, so that, as in the case of top yeasts, small aggrega- 

 tions of cells are formed, containing characteristic elongated buds 

 that are at once noted by the experienced observer. These cell 

 forms are chiefly found in the sediment, whilst the quick-growing 

 film, though initially of the same type of cells, afterwards consists 

 of a vegetation resembling mould with greatly elongated, radial 

 hyphse that partly develop into numerous yeast conidia and partly 

 disintegrate like Oidia. The mycelium of the film consists there- 

 fore of an intricate mixture of true hyphse, aggregated buds, bud 

 cells and Oidium cells. On solid media like wort gelatin, the 

 colonies resemble those of yeast, with a puffy, corrugated centre 

 and flat, fibrous rim, the growths resembling yeast cells being 

 situated in the central portions of the colony and the mycelial 

 forms in the outer portion. Monilia Candida is characterised by 

 considerable enzymatic power, and for a long time served as a 



