() clx>) 
type, they are of a fair size, a longish oval with a strong 
attachment peduncle, and have five rows of reticulations 
usually, though in certain cases I have counted six; they are 
colourless. In the secondaries the same hair-like scales also 
prevail considerably though they appear to be slightly finer 
than those in the primaries, whilst it should also be noted 
that they are entirely confined to the male sex, not being 
found in any of the female forms of the species. 
I do not find that the scales of the Plebevnae (in its broadest 
sense) that are brown in both sexes present structural differ- 
ences from those that are blue in one or both sexes; they 
appear to be essentially of the same type, they are ribbed 
similarly and are similar in pattern, allowing of course for 
specific divergence. 
The genus Heodes is very nearly allied to the Plebeinae 
and there is nothing specially to draw attention to in the 
structure and type of their scales. They have assumed 
patterns very similar to those we have been considering both 
as to shapes and apical terminations whilst their attachment 
peduncles are almost precisely the same, there are however 
two points in which they differ; they have no “ blasen- 
schuppen,” and though their copper hue is classed among 
structural colours, yet viewed under transmitted light the 
colour remains quite apparent; this is not the case with our 
European blues, they are always, so far as I have examined 
them, transparent under transmitted light and are somewhat 
yellowish; it must be remembered however that this is 
not so with many of the tropical species, but I propose to 
put before you a few observations on this difficult subject 
a little later on. 
Knowing that certain exotic genera that were magnificently 
blue in most of their species, and whose affinities I put rather 
nearer the Ruralinae than the Pleberinae, were devoid of 
“‘ blasenschuppen ” it was with much interest that I turned 
to the blue species of the genus Ruralis to see whether or not 
they would be found in them, naturally the first one to be 
examined was Ruralis quercis. 
The scales generally speaking are simple, the only ones that 
have serrated apices being those that largely compose the 
