FUNGUS DISEASES 91 



Panama and Costa Rica, though it has long been known 

 as the Panama disease, and although it also attacks 

 principally the Gros Michel variety. He bases this state- 

 ment on a comparison of Levy's description of the true 

 Panama disease with the symptoms of the Surinam form 

 as observed by himself. He proposes the name " Surinam 

 Panama Disease," to distinguish it from the form prevalent 

 in Central America. 



The principal symptoms of the Surinam disease are given 

 as follows : (1) The occurrence of yellow spots on the 

 leaves ; this is best seen in young plants ; it cannot be 

 taken as a definite symptom, as it may be occasioned by 

 other causes. (2) The sudden appearance of one or more 

 incompletely developed leaves. (3) Longitudinal splitting 

 of the external leaf-sheath. (4) In the most usual form 

 plants of six months or older, which have been previously 

 healthy, show a softening, ribbing, and folding of the heart - 

 leaf, provided no fruit is present. The older leaves break 

 off at the junction of the stalk and leaf -sheath, turn yellow:, 

 and die in a few days. The plants are quite dead a few 

 weeks later. When fruit is present, the trunk remains 

 with the bunch at the top, but the fruit is without value, 

 as even when it is apparently ripe it has no taste. The 

 root systems of diseased bananas do not appear to be less 

 strong than those of healthy plants. 



On cutting open a diseased bulb it is seen that the 

 vascular bundles are discoloured brown, and that the dis- 

 coloration extends into some of the bundles of the leaf- 

 sheath as well as, in some cases, into certain of the 

 vascular strands of the roots. The central portion of the 

 bulb may commence to rot when the disease is in an 

 advanced condition, but the outside remains firm for some 

 time. The main differences between this description and 

 that of Levy are that there are no external symptoms of 

 disease in the roots, that the plants dry up and do not 

 rot, and that there is no smell. The absence of rotting in 

 the bulb is a particularly noticeable point of difference, 

 except in the final stages of the disease. 



