J: 
JOURNAL OF VARIATION. 
No. 11. VoL. II. 
November 16 th, 1891. 
THE GENUS ACRONYCTA AND ITS ALLIES. 
By Dr. T. A. CHAPMAN. 
{Continued from page 175.) 
CRONYCT A ( Cuspidia) strigosa . — I have had infer- 
tile eggs, larvae, pupae and imagines of this species 
for several years, but had completely failed to get 
fertile eggs until this year, when Mr. Farren of 
Cambridge sent me a moth which laid over two dozen eggs. 
In 1890, for example, I had a number of pupae and obtained 
nine moths. Among these moths, sleeved over a growing 
thorn bush, nine pairings were observed to take place, but in 
no instance with a satisfactory result. I believe others have 
been more successful, and am therefore unable to say wherein 
my procedure was faulty. Aini sometimes pairs in the same 
useless manner and did so in every instance in 1890, whether 
I or the season was to blame in either or both instances I 
cannot say. In previous years the same arrangements had 
been very successful with alni. The egg is the smallest of the 
AcroJiyctas, being only 74 mm. in diameter and is transparent 
and colourless; the structure is that of the other species of the 
genus, the ribs about 41 in number. The inner egg shrinks 
away from the outer, leaving a clear margin, but, the inner egg 
remaining colourless, this is not so self-evident as in the 
coloured species. In eggs laid on glass the development of 
the larva is easily observed. When ready to hatch, the larva 
presents very little colour except the brown jaw tips, a faint 
indian ink in the head, and indications of brown round the 
margin where the dark segments lie, can just be made out ; 
the position of the larva in the egg-shell being identical 
with that of psi, tridens and all the other Acronyctas so far 
as I have observed, viz.^ with the head under the vertex 
