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Remarks on Miscellaneous Subjects. By J. McClelland. 



I. On a species of Aphis destructive to indigo, PI. xi. fig. 1. 

 — In the Jessore district, we have been informed that the 

 indigo this year suffered severely from a blight ; we have not 

 heard whether this has been general, or if it has only been 

 confined to particular lands, nor have we had any particular ac- 

 count of the period at which the blight appeared, or the kind 

 of weather that preceded it. The river, however, we know to 

 have been unusually high, and to have done considerable 

 injury to crops situated in low grounds, from which we should 

 infer that it was the higher lands that suffered from the 

 blight, the inundation being sufficient we should suppose, to 

 account for any injuries that could happen to the plant in 

 low grounds. Having been informed that an indigo plant 

 in Mr. Thomas's garden, in Park Street, was affected in a 

 manner exactly similar to that of a considerable proportion 

 of the indigo crop in Jessore and the Midnapore districts, I 

 visited the garden, and found a single indigo plant in 

 the midst of a shrubbery having all its leaves, particularly 

 the younger ones, puckered and drawn together like the 

 frill of a cap. To common observation this appeared to be 

 the effects of blight, but as no other plant in the shrubbery 

 was affected in the same manner, it at once became appa- 

 rent from this, that the injury was occasioned by some insect ; 

 and on minute inspection, the larvae of a species of Aphis, or 

 rather Gallinsecta of Degeer (since they appear to have but 

 one articulation in the tarsus) was seen. Fig. 1, plate xi. is a 

 magnified representation of the insect in its nymph stage ; its 

 natural size is little larger than the point of a pin. The perfect 

 insect I have not seen, but among the Aphides the larva 

 is said to differ but little in appearance from the parent. 

 To the naked eye the larva? appear to be contained in a 

 minute hairy secretion deposited on the upper surface of 

 the leaf, causing it to contract and curl up, and the plant to 



