42 



species of insect?. He says of it ti i in full bear- 



" ing commence to fail in a few weeks ; all the leaves fall down, and 

 " the centre falls off. No beetle or worm is to be found ; the disease 

 '' seems more like what id known as plantain disease "( 1 1). In a pamphlet 

 published at Georgetown and not generally accessible, he gives the 

 following account:— '• My first dissection of a tree diseased from blight 

 u led me to suppose that the cause of the disease was the attack of the 

 " weevil in question [presumably the Palm Weevil, though not tnen- 

 M tioned by name]. The part of the stem immediately under the 

 " cabbage portion was completely riddled by this insect, and hundreds 



" of grubs, in all stages of development, were found On 



" dissecting the top of the tree, all the fruit germs were found quite 

 " rotten (putrid ferm .■ntati..n\ and gave a most offensive smell, and at 

 '■ the point where the last frond or central spike divides from the 

 " lower fronds, the state of putrefaction was fearful. Fortunately, 1 

 " decided upon trying another tree. This time the stem was perfectly 

 " sound, and without a speck; but on dissecting upwards, and care- 

 " fully removing each frond and its integuments, the outer part was 

 " found to be more or less tainted, and the fruit stalk from which the 

 " fruit had fallen was quite offensive. As the top of the tree was 



" the integuments of each frond being removed, the cabbage in the centre 

 " was quite sound, so that I could eat the centre to within six inches 

 " of the diseased point, which, when reached, was quite as putrid as 

 " my first specimen. The crimped form of the bottom of this central 

 " spire left uo doubt on my mind that the seat of the disease was at 

 " that spot, and that there had been abundance of vitality in the lower 

 " part of the tree to send forth the central shoot until the parts im- 

 " mediately in contact with the putrid matter were poisoned by it. A 



" without finding a trace of an insect, even with the aid of a powerful 

 " magnifier, and afterwards under the microscope. One small beetle 

 " was found on one subject which is before you, and was named by my 



" friend, Dr. Whitlock. as Papains tridens Seeing that 



" only one specimen of this diminutive beetle was found in my many 

 '• investiirations. I can scarcely believe that the disease can bo attribut- 

 " able to it "(15). What insect is meant is not clear. The generic name 

 is obviously a misprint for Passtthis, but Pasadus ( pri ocae mis) tridens, 

 Wied. is a native of Malacca, &c. The Passali lay their eggs in 

 decayed wood, and are harmless. Specimens of the diseased trees, 

 preserved .and sent to Kew, were carefully examined by Dr. M. C. 

 Cooke for injurious fungi. His search resulted in the description of 

 several new species, but he could not find one that appeared to be the 

 true cause of the disease. Since 187(> the study of disease-producing 



infectious and sj 

 , F.L.S., Directoi 



his report in the Bulletin of the Botanical Depart- 

 Iso advisable to give in full, is as follows :— 

 ere cut down, and the roots, stem, leaves, and cabbage 

 w:ts no evidence whatever of attacks by a beetle ; 



