214 Miscellaneous. 



the most part diseased, wherever planted. These conflicting opinions 

 must be cleared up by experiment. In the meantime, I believe that 

 I can point out the " seat of the disease," which is at all events the 

 first step towards the discovery of its cure. If a plantain tree be 

 stripped of its leaves from the root upwards, it will be found to con- 

 sist of a number of joints — the bunch of plantains being a continua- 

 tion of the upper joint, and the spire being the upper leaf rolled up 

 — exactly similar to a cane and its arrow — the bunch being the or- 

 ganic apex of the plantain tree, in the same manner as the cane 

 arrow is the organic apex of the cane plant. 



Of the various vessels and tissues which are necessary to vegetable 

 life, the plantain tribe abounds in what are called spiral vessels or 

 tracheae ; and if a healthy plantain tree be examined from the root 

 upwards as far as the fruit, these vessels will be found in continuous 

 lines ; and even in the farina of the plantain they are detected in an 

 extreme state of tenuity. On further examination, these spirals (as * 

 has been known to botanists for some time) are found to be com- 

 posed of numerous fasciculi, and are contained in tubes from whence 

 they can be drawn forth, having a translucid appearance, and being 

 perfectly free from any adherent matter. From the large number of 

 these vessels in the plantain tribe, it is evident that their functions 

 must be important, and that any impediment to their healthy action 

 must be attended with an imperfect development in some part of 

 the plant. Now if a plantain tree bearing a bunch of plantains in a 

 more or less diseased state be examined carefully, a certain number 

 of these tubes containing spirals from the roots up, through the culm 

 or body of the tree into the bunch, will be found to be filled with a 

 ferruginous-looking fluid of a more or less dark colour, and if the 

 spiral vessels be drawn forth from their tubes, this matter will be 

 seen to collect upon them in minute drops ; the spirals will also be 

 of the same colour as the substance contained in the tubes. A bunch 

 of plantains in the extreme state of disease, containing no farina, but 

 merely the dissepiments of the cells, will have a large number of the 

 spiral tubes, particularly in the circumference of the culm, filled with 

 a dark ochreous-coloured fluid, while the number of diseased tubes 

 will be fewer, and the colour of the fluid contained more of a yel- 

 lowish colour, in less diseased plants. 



In the stock of a small poor bunch of plantains, but still contain- 

 ing farina and edible, only a trace here and there of the abnormal 

 matter was found. This peculiar state is not confined to the full- 

 grown plant, but the youngest suckers show the disease in a greater 

 or less degree. All the other tissues and vessels of diseased trees I 

 have found after the most careful investigation to be quite sound. 

 The decay of the leaves, and subsequent rottenness and destruction 

 of the plant, is owing to its diminishing vitality, and has nothing to 

 do with the specific disease. Any mechanical injury sufficiently vio- 

 lent to diminish the vigour of the plant, would be followed by simi- 

 lar decay and rottenness. I am therefore fully convinced, that, what- 

 ever may be the cause of the disease, the seat of it is in the tubes 

 containing the spiral vessels, which are invaded by an abnormal 



