SCIENTIFIC SOCIETIES. 195 
a new species coming nearest to Erupa (?) titanalis, Felder and Rogenhofer, 
Reise d. Nov., pl. exxxvii, fig. 4. 
Mr. R. M. Christy, who was present as a visitor, read the following 
note :— 
“As requested by my friend Mr. Wm. Cole, I wish to bring under 
your notice what I think will be regarded as a remarkably obvious case of 
naturally protective colouring. T was in America in the autumn of 1883, 
and on the 26th August, near Carberry, Manitoba, I found a large larva 
feeding ravenously on the leaves of a small bush (Eleagnus argentea), which 
is common on many of the drier parts of the prairies of the Canadian North- 
West. A short search brought to light quite a number of others, all feeding 
on the leaves of the same bush. These I carefully kept, and in due time 
they entered upon the pupa Stage, enclosing themselves in hard brown 
pear-shaped cocoons open at one end. Unfortunately, however, the mature 
insects emerged last spring (1884), while I was again away in America, 
with the result that Iam now only able to exhibit two very dilapidated— 
instead of two very handsome—specimens of that local form or subspecies 
of Platysamia columbia which is peculiar to the prairies of the Canadian 
North-West, and which has very recently been named Platysamia columbia 
uokomia by my friend Mr. Brodie, of Toronto, in accordance with the 
trinomial system of nomenclature so general across the Atlantic. 
“TI have brought up for exhibition specimens of Eleagnus argentea. 
It will be observed that the leaves are of a very peculiar pale silvery green 
colour, quite unlike that of the leaves of most other shrubs. TI have also 
brought for exhibition a coloured drawing of the full-grown larva of the 
insect, made by my friend Mr. E. E. T. Seton, of Toronto. It is observable 
that the colour of the larva exactly corresponds during life with that of the 
leaves of the food-plant; and, as these themselves are of an unusual colour, 
I think it may be regarded as an obvious case of naturally protective 
colouring.” A description of the larva followed. 
Mr. Christy also exhibited a twig of Betula glandulosa, and made the 
following remarks thereon :— 
“On the 7th August, 1883, as I was crossing a very extensive swamp, 
covered with trees of spruce and tamarac, and lying on the banks of Pine 
Creek, Manitoba, I observed a butterfly, either belonging to, or closely 
allied to, Papilio asterias, fluttering over the bushes, evidently in search of 
flowers. As I watched it, it settled momentarily, and exactly as if it had 
mistaken it for a yellow flower, on a twig of Betula glandulosa, Mich., 
bearing withered leaves of a light yellow colour. This identical twig I now 
exhibit. There were other similar twigs on the same bush. Of course I am 
perfectly well aware that it is impossible to say for certain that the insect 
mistook the leaves for a yellow flower; but it certainly settled upon them in 
such a manner as to leave little doubt on my own mind that they did so,” 
