AGROTIS NIGRICANS. 19 



Agrotis NIGRICANS. 

 Plate LXXII, fig. 1. 



On May 11th, 1865, Mr. Doubleday kindly presented 

 me with some larvae, which proved to be of this 

 species ; and to that gentleman I am greatly indebted 

 for the following account of their destructiveness in 

 a field of ten acres, which last autumn was sown with 

 wheat, and with clover in the early part of this year ; 

 the clover came up well, and the field was green with 

 it all over, until these larvae began to attack it. So 

 prodigious were their numbers and so great their 

 powers of devastation that, by the 17th May, not a 

 leaf of clover, nor even of any weeds, remained out of 

 the whole ten acres, though the wheat was uninjured ; 

 and by that time they had left the open field and gone 

 to the hedge-banks and ditches, where a remarkable 

 scene of destruction presented itself to view. The large 

 Heracleum and other umbelliferous plants were stripped 

 of their leaves, and, in short, nothing was left but 

 grasses, which they did not appear to touch. 



I also received other larvae of this species on the 

 14th May from Mr. Last of Ipswich, feeding on 

 Plantago major and P. lanceolata, and he reported 

 that they liked a change of food, and would eat many 

 low plants ; however, I found they took readily to 

 clover, and, like those before mentioned, continued to 

 feed to about the middle of June, the moths appear- 

 ing from July 15th to July 24th, varying much in their 

 appearance, and becoming active and restless the 

 moment their wings were dry. 



The larva when full-grown is an inch and a half 

 long, smooth and cylindrical. The colour of the back 

 is ochreous-brown, and in some individuals very bright 

 ochreous ; a thin grey dorsal line, margined with 

 blackish, and running through a series of blackish- 

 brown triangular and diamond shapes, well defined in 

 some individuals, though obscure in others. 



