416 
NATURE 
[JUNE 20, 1912 
calculating its effective or self-capacity on the assump- ] the laws with regard to birds were sufficient, if ad- 
tion that the whole steady current inductance of the 
coil is effective even when it is oscillating freely. 
This capacity is then added to the capacity of the air- 
condenser. Another method of finding the required 
correction by comparison of the results obtained on 
the overlapping portion of the ranges of two coils is 
also described. The correction can be made small by 
suitably designing the coils—Dr. W. H. Eccles: 
Applications of Heaviside’s resistance operators to the 
theory of the air-core transformer and coupled circuits 
in general. In circuits possessing constant induct- 
ance, resistance, and capacity the differential equations 
for the currents and the voltages are linear with 
constant coefficients, and may therefore be solved by 
aid of the known simple properties of symbolic 
operators. The symbolic operator method proves to 
be very compendious in problems concerning the 
determination of the primary and secondary currents 
and voltages of transformers whenever the applied 
E.M.F. can be expressed as an exponential function 
of the time, or when it consists of a sudden applica- 
tion of a constant or an exponential function, and 
also when it is impulsive. In the paper the method 
is first applied to a pair of “indirectly ” coupled cir- 
cuits—i.e. circuits that are insulated from each other. 
—C. R. Darling: The movements of semi-oily liquids 
on a water surface. The effect produced when a 
drop of liquid is placed upon a clean water surface 
is considerably modified if the liquid be slightly 
soluble. Whereas a drop of oil spreads and forms a 
permanent film, slightly-soluble liquids form films 
which afterwards break into globules, which, if a 
certain minimum size be exceeded, break up into 
smaller globules, until a state of equilibrium is 
reached. The division of the films or globules is 
produced by indentations which spread until partition 
has taken place. This indentation gives to globules 
a reniform shape; and in certain cases the distorted 
globules are projected violently across the surface of 
the water. The effects differ in intensity with 
different liquids, and phenomena peculiar to a given 
liquid may also be noted.—G. L. Addenbrooke: Sur- 
face leakage experiments with alternating currents. 
Experiments on dielectrics at different temperatures 
and over a wide range of periodicity showed that the 
losses found were in some cases partly due to surface 
leakage. When this latter was eliminated and the 
data obtained with the surface leakage and without 
were compared, it did not seem as if the portion of 
the losses due to surface leakage could be accounted 
for by assuming that it was constant at all periodi- 
cities, as is the case with the losses in metallic con- 
duction. Measurements were therefore made _ to 
ascertain the behaviour of the surface leakage alone. 
The relative losses with an alternating current of 42 
periods and a continuous current were measured, the 
pressure being the same in both cases. In the case 
of glass the relation losses with continuous and alter- 
nating currents were about as 1 is to 3, 4, or 5. A 
much higher ratio for the losses was found for ebonite 
—namely, 1: 40. Further experiments show that the 
moisture present must be in a very attenuated state 
for the differences in the losses found to become 
sensible. Ordinary -water, even in very thin films, 
does not show the effect. 
Zoological Society, June 4.—Mr. E. G. B. Meade- 
Waldo, vice-president, in the chair—Mr. E. G. B. 
Meade-Waldo introduced a discussion on the preserva- 
tion of the native fauna of Great Britain, in which 
Mr. A. Heneage Cocks, Dr. F. G. Dawtrey Drewitt, 
and Mr. Stewart Blakeney (who sent a written con- 
tribution) joined. The necessity of creating public 
opinion on the matter was urged. It was agreed that 
NO. 2225, VOL. 89] 
2225; 
ministered strictly. With regard to mammals, it was 
the opinion of those present that the use of steel 
traps, instead of snares, for catching rabbits was 
chiefly responsible for the extermination of wild cats, 
martens, and polecats in many parts of the country, 
and ought to be suppressed.—R. Lydekker: A new 
local race of giraffe from the Petauke district of 
north-east Rhodesia.—Miss Helen L. M. Pixell: Poly- 
chzeta from the Pacific coast of North America. Part 
i. This paper contained a description of Serpulidz 
from the Straits of Georgia, chiefly the Departure 
Bay Region of Vancouver Island, together with 
some specimens from Victoria and Puget Sound, 
eighteen species in all, of which five were 
new.—R. I. Pocock: Antler growth in_ the 
Cervida, with special reference to Elaphurus and 
Dorcelaphus. It was pointed out that the growth of 
the individual antler in Elaphurus, as shown by a 
series of sketches supplied by Lord Tavistock, proved 
that the anterior and posterior branches of the antler 
of Elaphurus were homologous with the brow-tine 
and beam of the Sambar’s antler, and that in Dor- 
celaphus the sub-basal snag was the homologue of 
the brow-tine in the old-world deer, as Sir Victor 
Brooke claimed.—Dr. Hans Gadow: The one-sided 
reduction of ovaries and oviducts in the Amniota, with 
remarks on mammalian evolution. The reduction began 
with the oviduct, and a first cause of the invariably 
right-sided bias had to be looked for in the turning 
of the embryo upon its left side, a position which 
influenced the growth and relative position of the 
stomach and primary intestinal loops, these being 
stowed in the abdomen in such a way that they were 
less disturbed by an egg passing through the left than 
through the right oviduct. In the Monotremes also 
only the left ovary and duct were functional, although 
those of the right side were structurally not affected. 
This was not a case of reptilian inheritance. Proto-, 
Meta-, and Eutheria represented a continuous, mono- 
phyletic line of evolution, with the Monotremes and 
Marsupials as offshoots.——Dr. F. E. Beddard: An 
asexual tapeworm, obtained from the musquash (Fiber 
sibethicus). This showed a new form of asexual pro- 
pagation; a sexual worm believed to be the mature 
form of the same tapeworm was also described.—Dr. 
W. Nicoll: Two new Trematode parasites from the 
Indian cobra (Naja tripudians). The first was found 
in the gall-bladder and was made the type of a new 
genus of the family Dicrocoeliida. The second was 
found in the ureters, and represented a new species 
of the genus Styphlodora.—Dr. R. Broom: Some new 
fossil reptiles from the Permian and Triassic beds of 
South Africa.—Prof. S. J. Hickson: The Hydrocoral- 
line genus Errina. The genus was founded by Gray 
in 1835, and since that date two other genera (Labio- 
pora and Spinipora) closely related to Errina had been 
described. An analysis of the characters of these three 
genera was given. Two new species were described, 
one from New Zealand waters and the other from the 
Cape of Good Hope. 
Linnean Society, June 6.—Prof. E. B. Poulton, 
F.R.S., president, in the chair.—Prof. A. Meek: The 
development of the cod, Gadus morrhua. The author 
| sought to demonstrate by photographs of sections that 
the gastrula arises by the delamination of the dorsal 
entoderm, and that the latter is at once differentiated 
into an embryonic and a yolk-sac portion (periblast).— 
C. Hedley: Palwogeographical relations of Ant- 
arctica. It is suggested that a link between Antartica 
and Tasmania was the latest extension .of the southern 
continent, existed during the last warm phase, and 
transmitted to Australasia a fauna and flora of South 
American origin; that Antarctica then supported a 
