Monthly Mlcroscoplcall 
Journal, Dec. 1, 1869. J 
of some of the Lepido^ptera. 
315 
proposes to call the new genus Prioneris, from the saw-like struc- 
ture of the costal margin.* The only other species of Pieris which 
I have examined without finding plumules are Agathon, Protodice, 
and Callidice ; the absence is very remarkable in the two latter, as 
their allies Daplidice and Hellica are abundantly supplied therewith. 
There is a group of this genus to which I did not allude in my 
first paper, being then doubtful whether its scale could be con- 
sidered a plumule — that is, of a character serving for distinction ; 
such scales are very abundant on P. Lycimnia, Flipjpantha, Isandra, 
and some congeners, showing that these are perhaps all varieties of 
one insect. There is a figure of it on Plate XXXIY., Fig. 7 ; and 
great has been my surprise to find a somewhat similar form in 
some members of the Danaidse family, to which further reference 
will be made ; these have not the bulb-and-socket apparatus. 
The interlinking of affinities, and the manner in which Nature 
loves to repeat her works with variations, are strikingly shown in 
the plumules generally ; and throughout the different families there 
may be observed assimilations of form existing in widely-separated 
groups, just as is the case in the insects themselves. 
Plumule is not an appropriate name for some of the forms of 
the scales which serve for distinctive classification ; nor is battle- 
dore, which has been applied to those of the Lijcsena genus; a 
more universal name would be better, proclaiming their private and 
peculiar property ; and I would suggest Idiolepides (from Ihto^ 
private and pecuhar, and Xeirh, a scale) ; but we will at present 
continue the former term, plumules. 
Before entering into a relation of the families and genera in 
which these objects are found, let me say something about them 
specially for microscopists. I have before described them as rotund 
or cyhndrical ; but a term suggested by Mr. Sidebotham, viz. 
bellows-shaped, is more characteristic and correct. It is manifest 
that, if the form of plumule of P. Pajpse were actually rotund or 
cylindrical, the peduncle and bulb would often, on a slide, be 
covered with the membrane ; but, when mounted, the scale always 
shows the lobes on each side of* the bulb, proving its, in some 
degree, appressed form. 
Then, as to the parts of the insect where they are to be found : 
generally on the upper surfaces of the wings, sometimes most 
abundant on the primary, sometimes on the secondary ; usually in 
or near the discoidal cells of both wings ; but occasionally very 
strangely placed, as we shall presently see when referring to the 
genus Euploea. 
The best way of collecting and mounting is by gently pressing 
the wing of the insect against a glass slide, by which means a 
sufficient quantity of the scales will adhere : to get a clean mounting 
* It is interesting to note that a similar serrated costa occurs in some species of 
Fapilio, of Charaxes, and of Gonepteryx ; and these are all without plumules. 
