1881. 129 



almost as much certainty of finding it as in Nematus ventricosus ; at 

 any rate, in the spring and early summer months. I have not yet 

 met with Q. polygoni, but would be glad to obtain eggs of it at the 

 proper season. 



Finally, I must call attention to the seeming purposelessness of so 

 much parthenogenetic fertility in G. raphani. The sexes always ap- 

 pear to be present in about equal numbers, and one male is able to 

 fertilize many females. It would appear to be without any place in 

 the economy of the insect analogous to that of bees and wasps, ac- 

 cording to the theory of Dzierzon and Yon Siebold. It appears to 

 me rather the concomitant of a prevalent species supplied with 

 abundant food of a stimulating quality. 



Milford, Letterkenny, Ireland : 

 October, 1881. 



NATURAL HISTORY OF CR AMBUS WARRINGTONELLUS. 

 BY WILLIAM BTJCKLEK. 



Of this species I last year received two batches of eggs, the first 

 on the 14th of August from Mr. "W. H. B. Fletcher, and obtained by 

 him in the New Forest, and supplemented afterwards with a few more, 

 and the second batch six days later from Mr. J. Gardner, of Hartle- 

 pool, and to both friends I return many thanks. 



All the eggs were laid loose ; those from the South hatched on 

 16th of the month, and up to the 1st of September ; those from the 

 North began to hatch on August 27th, and had finished on the 29th. 

 The young larvae from these wide apart localities were kept separate, 

 and placed in pots with growing plants of Festuca duriuscula, Aira 

 jlexuosa, and some other grasses of a hard nature ; their progress was 

 noted up to the middle of November, when they began to close their 

 numerous galleries for hibernation, after having very considerably 

 ravaged the grass. 



In early spring of 1881, I noticed a great number of them busily 

 engaged in afternoons, whenever the sun shone on the pots, spinning 

 threads in all directions round the outside of the grasses which had 

 in the interval recovered in a great degree ; but for some time after 

 this I was unable to attend to them, until at length I observed the 

 grass to be nearly all dead ; then, when almost too late I had the 

 mortification to find the greater part of them had deserted their 

 quarters, though enough still remained to serve my purpose of figuring 

 the larvae and breeding the perfect -insects. 



