174 THE ENTOMOLOGIST. 
some instances nearly black. Specimens obtained in limestone 
districts are of a brownish grey colour. 
Arayvism.—In this class I place all variations which show a 
tendency to reversion to what I conceive to be a common 
ancestor. Of this I have a few illustrations in my cabinet, and 
singularly in that usually remarkably invariable species, Vanessa 10. 
Several of the Vanesside have a row of blue spots on the margin 
of the wings; these are well seen in Vanessa urtice, V. polychloros, 
V. antiopa, and several foreign species. In V.io the blue marginal 
spots appear to be concentrated in the under wings into two large 
circular patches; but by careful examination of specimens, taken 
by myself in the New Forest, I find some have on the lower 
wings small blue spots in the dark colour beyond these patches, 
which, to my mind, are evidently traces of the row of blue spots 
which in Vanessa io have become differently arranged. In the 
Larentide, a family commonly known as carpet-moths, the bulk 
of the species have a well-defined broad central bar; but this is 
more or less broken in some species, yet amongst them it is not 
unusual to find one with the centre bar well defined. This I take 
to be a case of reversion to the markings of a common ancestor. 
Cidaria corylata in the normal form has the bar interrupted; but 
I have a specimen in which it is as complete as is typical of the 
genus. In Melanippe hastata the bar is usually interrupted; but 
T have one in which the bar is complete. Melanthia rubiginata 
has usually only the commencement of the bar at the costal edge 
of the wings, but frequently traces of the obliterated bar are 
found on the inner edges of the wings. , 
DrworpuismM.—In this class I place all those insects which 
have two well-defined types of colour, generally without inter- 
mediate variations being found. ‘The best type of this class 
found in the British Isles is Argynnis paphia, and its dimorphic 
female form Valezina. In this case the normal coloration has red 
for the ground colour of all the wings, but in Valezina the ground 
colour is green. Although I have. spent many days in the New 
Forest in the observation of this species, I have never found a 
female of this insect which is other than either Argynnis paphia 
or A. valezina, yet I have found a green shade somewhat pervading 
the female of the former to greater or less extent. In Clisiocampa 
neustria dimorphism is well pronounced. I have both males and 
females of a yellowish buff, and of a dark brown colour. Colias 
