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PROCEEDINGS OE THE PERTHSHIRE SOCIETY OF NATURAL SCIENCE. 
artificially produced similar cones; so I am persuaded 
they are a mechanical result and not a physiological one, 
which a true tube would of course be. 
Another observation puzzled me for a long time. In 
gatherings from the bottom of our botanic pond, largely 
occupied by Tubifex, which were kept in large wide¬ 
mouthed specimen jars, I noticed that after a few days 
what appeared to be real tubes projected from the surface 
of the mud sometimes to the height of half or three- 
quarters of an inch. They were brown and not unlike the 
cones in my diagram, but the aperture—or, if I may so call 
it, the bore—of the tube was of a diameter very much 
greater than that of the body of the worm. I almost 
began to think that they might be worm-tubes after all, 
but by carefully watching them I soon discover the fabri¬ 
cator. It is the well-known blood-red larva of Chironomus 
plumosus, known as the “ Figure-of-8 worm,” or “the 
blood-worm.” It is common in our water-tanks, and 
every one must have noticed it at some time or other in 
their water-butts, probably making its way by a series of 
j erks, in which it al ternately contracts its body into a double 
loop like the figure 8, and stretches it out straight. 
Tnat there might be no doubt about this, I have kept a 
lot of them in very narrow vessels, thereby inducing them 
to make their tubes on the glass-sides of the bottle, so that 
their movements inside may be seen. I purpose writing a 
paper at some future time on the structure of these true 
tubes, which it is abundantly clear are not the work of our 
annelid Tubifex. 
I could multiply almost indefinitely the account of our 
many contrivances in keeping Tubifex, but you will, I 
hope, conclude that I have given enough evidence to show 
you that it is not a tube-maker. 
It may perhaps seem at first sight as if it were a matter 
of very little importance whether Tubifex rivulorum makes 
a tube or not. But to the physiologist studying worms it 
is of the greatest moment. A habit of tube-making is a 
certain step towards degeneration in an animal, and is ac¬ 
companied by modifications in the organs of circulation and 
respiration of the very greatest importance to the compara¬ 
tive anatomist. The habits of every animal are so related 
to its structure that you may on consideration think it 
not so trivial a matter to acquire accurate knowledge even 
on so small a detail as the subject of my paper. I hope I 
may be allowed to follow it further in my own person at 
some future date. 
May 7th, 1885. 
F. Buchanan Weite, M.D., F.L.S., President, 
in the Chair. 
Mr Robert Pullar, F.R.S.E., was appointed the Society’s 
delegate to the forthcoming meeting of the British Asso¬ 
ciation in Aberdeen. 
NEW MEMBERS. 
The following were elected :—Mr It. Stewart Menzies 
of Hallyburton, and Mr Leslie Macdonald, teacher, St 
Ninian’s, Perth. 
donations. 
The following were intimated :— 
Perthshire Collection. Grey hen—from Mrs Robertson, 
senior, of Struan; landrail—from Miss Scott, Kinclaven 
Crossing, Stanley; weasel—from Mr T. Marshall, Stanley; 
peregrine falcon and two fox cubs—from Sir Robert 
Menzies, Bart.; missel thrush—from Mr A. Steel, yr. of 
Blackpark; coal titmouse’s eggs and nest—from Mr R. H. 
Meldrum, Cherrybank; magpie’s nest and seven eggs, and 
missel thrush’s nest and eggs—from Colonel Drummond 
Hay of Seggieden ; common rat, and hedge-sparrow’s nest 
and eggs—from Mr F. H. White, Annat Lodge; fishes— 
from Mr D. Henderson, Dundee; Perthshire plants—from 
Mr R. Kidson, Stirling; wood from neolithic canoe found 
at Friarton—from Mr Wood, Friarton. 
Library. Five pamphlets from Mr H. Wilkie, Perth. 
The following papers were read :— 
1. “ Notes on a Supposed New British Willow .” By F. 
Buchanan White, M.D., F.L.S. 
The genus Salix, which includes the trees and shrubs 
familiarly known as willows, sallows, and osiers, is ad¬ 
mitted by all botanists to present very great difficulties as 
regards the definition and limitation of the species con¬ 
tained in it. These difficulties arise not merely from the 
great variability of the species, but also because the plants 
naturally and not unfrequently produce hybrids or crosses, 
many of which have been at one time or other considered 
to be good species, while even yet there is a divided opinion 
about some of them. Such hybrids would not perhaps 
present such great difficulties if they partoek of the char- 
