THE ENTOMOLOGIST. 87 
dull stone-colour, instead of reddish brown as in the type, 
which it resembles, however, in all other respects, as far as | 
have observed. Is this variety of common occurrence? It 
is mentioned in Newman’s ‘ British Butterflies, but is the 
first specimen I have ever seen myself, nor have I seen a 
report of its capture lately. I may add the insect was taken 
by my brother in a lane near Chatteris—A. Harold Ruston ; 
Aylesby House, Chatteris, February 17, 1875. 
Eupithecia Knautiata.—Perhaps you will allow me to 
make a few remarks on the Eupithecia which Mr, Gregson 
proposes to call Knautiata. In the first place I would point 
out that Mr. Gregson seems to have entirely overlooked 
Mr. Johnson’s letter published in the ‘Entomologist’ for 
January (Entom. viii. 22); and to me the information this 
gentleman gives seems most important. He says, “ that in 
former years heath grew abundantly at Bull’s Hill.” Now 
Mr. Gregson says that he has only found Knautiata at Bull’s 
Hill, where at the present time there is no heath whatever ; 
but at the other localities (Hawkshead, Witherslack, and 
Formby Moss), which he has visited, both the heath and 
Knautia arvensis were growing together; and on the heath 
only he found the Eupithecia minutata. From the above 
facts I gather that in former years both the heath and 
K. arvensis grew together at Bull’s Hill (as well as at the 
other localities); but from causes, which Mr. Johnson 
explains, the heath was gradually exterminated, whereas, 
apparently, the Eupithecia was not, and, as its usual food 
failed, it took to K. arvensis; and hence the slight difference 
in appearance of both larva and imago. In the second place, 
as regards the difference in colour, I imagine this would be 
nothing more than natural from the change in food. In fact, 
in the colour of the larve of many Eupithecie there is 
scarcely any characteristic difference at all; and from my 
experience (although I have not bred them in hundreds or 
thousands) the chief agency in affecting their colour is their 
food. With regard to such characters as “ stout,” “ thick,” 
“stumpy,’ “short,” &c., they can have but little value, 
unless the respective larva are compared at the same age. 
As far as I can judge, at present, 1 think Knautiata nothing 
more than a variety of Minutata; but if anyone will take the 
trouble to procure some eggs of Knautiata and feed the 
