458 THE RED STRING OF THE SUGAR-CANE, 



globular, it contains two globules which become four and then 

 eight. The spherical cell then divides, and each portion or 

 daughter-cell contains eight globules (PL xiii., fig. 6). These 

 globules are the forerunners of the spores; they are devoid of a cell 

 wall, for they coalesce to form one large globule upon applying 

 pressure to the cover glass. Within the growing or dividing cell 

 they are therefore naked, and only become covered when the 

 process of division ceases. When this occurs the spherical 

 aggregation of cells is a perithecium, the cells being the asci and 

 the outer walls of the peripheral layer of cells being the covering. 

 From the study of the paraffin potato sections, and of what 

 occurs when an immature or a mature perithecium is crushed, 

 it is clear that all the asci break doAvn with the exception of 

 those portions of the asci which constitute the covering of the 

 perithecium. Thus the mould, during the process of forming the 

 perithecium, passes through an ascigerous stage; in other words, 

 during its development it is a member of the Ascomycetes pro- 

 bably akin to Sj^hcerella, and when fully mature it is one of the 

 Sphseropsidese allied to Fhoma but differing in the absence of 

 conidiophores in the perithecium. 



When the mould is sown upon the surface of sugar-nutrient 

 gelatine in Petri-dishes there is formed first a white then a 

 crimson growth of aerial hyphas which may rise to a height of 

 3 mm. (PI. xiv., fig. 8). Upon potato or sugar-cane, small patches 

 of a rusty or pink colour sometimes appear in the white pile. 

 When the growth is white, uncharacteristic hyphse predominate, 

 while in the red growths the terminal cells of the aerial hyphse 

 are generally swollen to a flask-shape (PI. xiv., fig. 9). The con- 

 tents of the swollen cells may be hyaline or granular. In size 

 they vary considerably; on the surface of fluids such as Hansen's 

 glucose media they are small, while on sugar-gelatine the}'- are 

 large. In many cases the penultimate cell can be seen growing 

 into the flask-shaped terminal cell (PI. xiv., fig. 11), and there is 

 sometimes presented the appearance of the intergrowth becoming 

 a cluster of cells within the cavity of the terminal cell. The 

 intergrowth may emerge and continue to grow like an ordinary 



