Jfo, 4.] Miscellaneous Notes, 199 



"The tuunel is about the size of a quill, and is not at all straight. There can be no 

 doubt that the damage is caused entirely by the lopping of the trees, for in the forest 

 where the teak is not subjected to this ill-treatment the trees do not suffer in the least." 



Through the Officiating- Director of Agriculture in Assam were re- 



Eri silk-worms in ceived, in the latter part of August last, (1) speci- 

 Assam. mens of a caterpillar which had proved destructive 



to castor-oil plants, (2) specimens of Eri silk- worms (Atfacus ricini) which 

 had died of disease which had been very fatal to them in Cachar. 



The caterpillar proved to be the larvae of the Noctues moth, Achcea 

 melicerte of Drury, a species which has previously been reported as de- 

 structive to castor-oil plants in Lower Bengal and in Madras (vide 

 vol. I, pp. 52 and 104 of these Notes). The insect is a common one and. 

 occurs in India, Ceylon, Celebes, and Australia. 



With regard to the Eri worms, the disease appeared, on microscopic 

 examination of the contents of the digestive tract, to be Flacherie. The 

 chain ferments, Strepcococtus bombaycis, which is characteristic of Flach- 

 erie, being recognized on one of the slides that were prepared. Fer- 

 ments of this kind are always difficult to make out in alcoholic specimens, 

 so the not finding it in large quantities is not considered to affect the 

 probability that the disease was Flacherie, while Mr. Mackenzie's descrip- 

 tion of the symptoms, which were precisely those of the Flacherie of the 

 mulberry-feeding silk-worm (Bombyx mori), leaves no room to doubt the 

 correctness of the diagnosis. The fact is an interesting one, Flacherie 

 being so intimately connected with the fermentation of the mulberry leaf , 

 that it might have been supposed that it would not affect the Eri worm, 

 which feeds on a totally distinct plant. The well-known Pasteur system, 

 of dealing with the Flacherie of the mulberry silk-worm, is no doubt 

 equally applicable to the case of the Eri, and need not therefore be entered 

 into here. The following is extracted from Mr. Mackenzie's report, 

 dated 3rd August 1889 1 :— 



" During the past month (July) two very serious misfortunes have befallen the 

 enterprise. 



"(1) In the beginning of the month millions of caterpillars emerged from the 

 jungle and attacked the castor-oil plants, eating every leaf, bud, soft leaf-stalk, and even 

 parts of the barks. They arrived during the night, and when discovered next day 1 

 had overspread some three or four acres. All available hands were immediately put 

 on to picking them off the plants and killing them, and by evening, though many 

 thousands had been destroyed, the numbers left appeared scarcely diminished. Next 

 morning it was found that they (the caterpillars) had increased in numbers during the 



1 Since the above was written a series of excellent stained sections have been made, by 

 Mr. Wood-Mason, of one of the diseased caterpillars. These sections fail to show the 

 chain ferment, and the original observation therefore of its presence requires confirmation. 

 The most satisfactory subjects for examination would be live chrysalids raised from 

 deceased worms, the deceased worms themselves, preserved in alcohol, giving uncertain results. 



