JOURNAL OF VARIATION. 
No. 8. VoL. II. September 15th, 1891. 
THE GENUS ACRONYCTA AND ITS ALLIES. 
By Dr. T. A. CHAPMAN. 
{Continued from page 131.) 
CRONYCTA {Ctispidid) megacepJiala. — This species 
is most nearly allied to alni in one very important 
respect, viz., the distribution of the dark and pale 
segments of the newly-hatched larva. It also 
resembles it in the less important matter of living as a larva 
on the middle of the upper surface of a leaf. It presents an 
approach to leporina and aceris in the tubercles and their hairs 
becoming less marked as the larva gets older, in the surface 
hairs being very obvious, though very minute, and in the in- 
creased number of spines carried by the pupa. The resem- 
blance of the perfect insect to rumicis or auricoma, has, I 
think, been attained independently, as an instance, of allied 
species finding it possible and profitable to assume a similar 
facies ; or to express it differently, in tracing both back to a 
common ancestor, we should somewhere come across a form 
unlike the existing one, and more like, perhaps, tridens. 
The egg is the largest of any, being 1*23 mm. in diameter ; 
it is also a good deal flatter than any others. It is laid 
solitarily, but as the moth, when laying, is rather inclined to 
buzz about than to fly far, eggs are probably laid on neighbour- 
ing leaves (on the upper surface ?) more often than with other 
species ; when first laid it is of a pale greenish colour, uniform 
throughout, and when the dark dots first appear, the inner egg 
has not begun to shrink from the margin. When fully matured 
in colour, the colourless margin, due to the shrinking of the 
inner egg, is wider than in any other species and has the 
appearance of a frill round the egg proper, this great width is 
