Api-n, 1879] 241 



NATURAL HISTORY OF LTCJENA MED ON, HUF. ? (AGESTIS, OCHS.). 

 BY WILLIAM BUCKLER. 



"When Professor Zeller, in 1867, published his most interesting 

 history of this species at pp. 73-77, vol. iv, of this magazine, he stated 

 it to be generally accepted that Lyccena Artaxerxes is only a variety 

 of Medon ; and yet it appeared to him extremely improbable that the 

 larva of Medon should habituate itself to the food-plant of Artaxerxes. 



Since then I am not aware of any record of experiments made in 

 accordance with Zeller's suggestion, which induces me to offer the 

 following evidence in proof that the larva of Medon really does nourish 

 itself on the same species of food-plant in England as in Scotland. 



But, first in order of time, I have to mention that on June 3rd, 

 1877, Mr. J. E. Sobson, of Hartlepool, while searching Heliantliemnm 

 vulgare growing near the coast in his locality, found five larvae of a 

 LyccEiia, and at once very kindly forwarded them to me ; on com- 

 paring them with the figures I had taken of larvae of Artaxerxes in 

 1868, I found them to be in every respect precisely alike. These 

 larvae soon fed up on Heliantliemum, protected by a glass cylinder, and 

 they duly changed to pupae, two of them, unfortunately, were attacked 

 with mould, but the other three disclosed three differently marked 

 butterflies, viz. : on July 2nd, 5th, and 7th, these appeared respec- 

 tively to be Salmacis, Artaxerxes, and Agestis above, but to partake 

 most of Salmacis beneath. 



After this result, I became more than ever desirous of seeing 

 larvae of the typical Agestis from the southern downs, and it was not 

 many weeks before Mr. "Wm. E. Jeffrey most kindly put me in the 

 way of making their acqviaintance from the egg onwards, by his 

 capturing several typical females as they were flying over and alighting 

 upon Heliantliemum vulgare, on a Kentish chalk down. They readily 

 deposited their eggs on sprays of the plant, and I had the pleasure to 

 receive a share of them from my friend on 13th of September, when I 

 found them all laid on the under-sides of the leaves to which they 

 firmly adhered, singly, and in little groups of twos, threes, and more 

 together. 



The egg is smaller than that of ^gon, though very like it in 

 form and sculpture, being circular, flattened, with a central depression 

 on the upper surface, the shell covered with a coarse, prominent 

 reticulation, gradually becoming finer towards the nearly smooth 

 depression ; its colour, a pale greenish-drab, continues to the last. A 

 hole in the shell betrays the escape of the larva, which is a very slug- 



