260 PROCEEDINGS OF SOCIETIES. Roumil ?^uTiff 
shire, wliere Mr. Mudd (now of the Botanic Gardens, Cambridge) 
collected it in 1862. Ba-mac-dhui, tlie loftiest of the Cairngorm 
range, produces several very rare species abundantly, viz. : — 
Polytrichum sexangulare. Dicianum arcticum Sch. (D. 
Audreoea nivalis. Starkii molle Wils). 
„ grimsulana. Hypiium molle Dicks. 
The last-named species was, until very recently, almost unknown to 
botanists generally, and is still, as regards its synonomy, enveloped in 
considerable doubt. 
Short as the preceding sketch is, it will suffice to show the great 
difference between the micaceous mountains of Perthshire and the 
slaty and granitic ones of Braemar. Either region will richly repay 
the naturalist who may devote his time to its exploration, whilst the 
scenery around him must excite his intensest admiration, and of itself 
will amply repay him for a visit. 
Mr. John Watson exhibited upwards of 200 drawings from slides 
sent by him to Mr. Tuffen West, hereafter to be lithographed with 
others for his intended treatise on the plumules (so called) of the 
Lepidoptera ; they were principally of the Pieridce family, all being 
drawn by the camera to one magnifying scale of 350 times linear 
measurement. 
He also showed a number of these insects which yield the plumules, 
and drew attention to their similarities and differences ; noticing that 
some butterflies, closely allied in all other respects, display correspond- 
ing but distinctive resemblances in this also, while others as nearly 
allied possess very different forms of plumule ; and that the size of the 
insect does not govern the size of the plumule, some large species 
having small plumules, and some small species having large plumules ; 
some striking examples of these facts v/ere exhibited. About thirty 
species of the insects themselves, with drav/ings of their own plumules 
placed by their side, afforded an easy nicde of observation of the 
marvellously varied types of form displayed in these curious scales. 
Besides the drawings of the Pieridce family were a few of the 
PanaidcE (genus EupJoea) and NymplialidcE, and Mr. Watson expects 
to exhibit shortly a large number of drawings from these families, and 
from the Heliconidce, SoiyridcE, and Lyccenidcs. He drew attention to 
some hair-like scales tufted at their apex, which occur on some species 
of the genus Argynnis (to one of which he had previously alluded in 
his last paper), and showed drawings of them side by side with the 
true plumules and specimens of the insects themselves, from which 
both were taken. Whether or not these hair-like scales possess value 
for the determination of species is at present uncertain, but there can 
be no doubt of the plumules wherever found in all genera serving for 
that purpose. 
The feathery tip of the plumules is very fragile — more so in some 
species than in others : slides are often covered with the debris ; the 
drawings cannot represent their natural luxuriance in life. 
