34 



I cannot feel sure that this yeast is not a contributory cause of the 

 scabbiness, through its action on the tissues first opened up by the 

 attacks of the scab-fungus. The form of this yeast as procured from 

 cultures in infusion of banana-peel are shown in Fig. 55. 



Owing to the possibility that this yeast is a contributory factor in 

 the disease, a few words with regard to it are not out of place. 



When first removed, and therefore the result of what may be 

 termed dry growth, in contradistinction to the culture growth 

 soon to be mentioned, the cells of the yeast 

 |) QS> are usually very small and nearly spherical. 



The cells are seldom obtained in a budding 

 condition under these circumstances. While 



Fig. 55.-Yea*t cultivated from a vacuole ^ sometimes be seen it is not a 

 banana scab. prominent feature. After a few hours culti- 



vation in an infusion of banana-peel the cells 



appear larger, and often present a very distinct and bright vacuole 

 near the side or end of the cell. 



On being allowed to remain in the infusion for twenty-four hours 

 this yeast buds vigorously, giving rise to such forms as are shown 

 in Fig. 55. The longest chain seen consisted of seven spores ; but 

 such chains were very rare. After the growth had proceeded for a 

 while in the infusion, the vacuoles assumed a more central position, 

 and became less conspicuous. 



These yeast cells are never found in the interior of unbroken 

 pustules, although they are often to be found in those that have only 

 recently burst. 



From this it follows that this yeast must be regarded as one that 

 lives on the surface of the banana, and on the sweetish and gelatinous 

 exudations originating in the ruptures produced by the fungus 

 causing the pustules. It may be that this is the race of yeast utilised 

 in the production of banana wine. 



It will be seen that a marked feature of the disease as here 

 described is the fewness of the spores to be found in the cavity of the 

 perithecium, and the fineness of the mycelium. The preparations have, 

 however, shown in a satisfactory manner that such spores are produced 

 in the perithecium from minute basidia, after the manner of those 

 fungi referred to the genera or " collections," Phoma, Myxosporium^ 

 &c., and there can be little hesitation in assuming that the broad 

 relationships of the fungus are thus made out. 



A number of fungi of this nature, inhabiting the banana plant r 

 have been described from different parts of the world ; but seldom 

 with sufficient completeness to give the descriptions much value, and 

 when one has spent valuable time in hunting up such literature, it 

 may occur to him to doubt the advisability of encumbering the 

 nomenclature with a further addition, even if it be as the result of 

 extended investigation, especially in view of the established 

 uncertainty of the general relationships of many of the allied forms. 



" A rose by any other name would smell as sweet"; doubtless thi& 

 fungus, fitted with a Latin name, would spoil just as many bananas. 



