Nov. 3, 1881] 
NATURE 
23 
mens of Zguanodon in the British Museum, however, show that 
these elements of the pectoral arch were present in that genus. 
Some other Dinosauria possess clavicles, but in several families 
of this sub-class, as I regard it, they appear to be wanting. 
The nearest approach to birds now known would seem to be 
in the very small Dinosaurs from the American Jurassic. In 
some of these the separate bones of the skeleton cannot be dis- 
tinguished with certainty from those of Jurassic birds, if the 
skull is wanting, and even in this part the resemblance is strik- 
ing. Some of these diminutive Dinosaurs were perhaps arboreal 
in habit, and the difference between them and the birds that 
lived with them may have been at first mainly one of feathers, 
as I have shown in my Memoir on the Odontornithes, published 
during the past year. 
It is an interesting fact that all the Jurassic birds known, 
both from Europe and America, are land birds, while all from 
the Cretaceous are aquatic forms. The four oldest known 
birds, moreover, differ more widely from each other than do any 
two recent birds. These facts show that we may hope for most 
important discoveries in the future, especially from the Triassic, 
which has as yet furnished no authentic trace of birds. For 
the primitive forms of this class we must evidently look to the 
Paleozoic. 
SCIENTIFIC SERIALS 
Journal of the Asiatic Society of Bengal, vol. 1. part 2, No. 2 
1881 (July 30), contains :—H. F. Blanford, F.R.S., on the rela- 
tions of cloud and rainfall to temperature in India, and on the 
opposite variations of density in the higher and lower atmo- 
spheric strata, and description of a rain-gauge with evaporimeter 
for remote and secluded stations (plate 15).—J. Wood-Mason, 
on some insects belonging to the Rhopalocera from India and 
Burmah.—W. T. Blanford, F.R.S., on the Voles (Arvicola) of 
the Tibet Himalayas and Afghanistan (plates 1 and 2); and on 
Myospalax fuscicapillus, Blyth. 
Gegenbaurs morphologisches Fahrbuch, vol. vii., part 2, 1881, 
contains—R. S. Bergh, on the organisation of the cilio-flagellate 
Infusoria ; a phylogenetic study ; plates 12-16. Contains dia- 
gnoses of the genera Ceratium, Dinophysis, Protoperidinium 
(noy. gen.), Peridinium, Protoceratium (nov. gen.), Diplosalis 
(nov, gen.), Glenodinium, Gymnodinium, Polykrikus, and Pro- 
tocentrum, with descriptions of several species in each.—Dr. W. 
Pfitzner, on the minute structure of cell-nuclei.—Prof. Bischoff, 
on the third or lowermost frontal gyrus(Stirnwindung), and the 
inner upper lobulus-parietalis gyrus in the gorilla. 
Zeitschrift fiir wissenschaftliche Zoologie, August, 1881 (vol. 
xxxvi. part I), contains ; Dr. H. Simroth, on locomotion and the 
organ of locomotion in Cyclostoma elegans and other indigenous 
land and freshwater mollusca (plate 1 and many woodcuts).—Dr. 
P. Stohr, on the development of the skull in the Anura (plates 
2 and 3).—Dr. A. Gruber, on division in the monothalamous 
rhizopods (plates 4 and 5).—F. Blockmann, on the development 
of Neritina fluviatilis (plates 6, 7, and 8).—Prof. W. Krause, on 
the human allantois (plate 9). 
SOCIETIES AND ACADEMIES 
MANCHESTER 
Literary and Philosophical Society, October 4, 1881.— 
J. P. Joule, F.R.S., &c., in the chair—On drops floating on 
the surface of water, by Prof. Osborne Reynolds, F.R.S. It is 
well known that under certain circumstances drops of water may 
be seen floating on the surface for some seconds before they dis- 
appear. Sometimes during a shower of rain these drops are 
seen on the surface of a pond, they are also often seen at the 
bows of a boat when travelling sufficiently fast to throw up a 
spray. Attempts have been made to explain this phenomenon, 
but I am not aware of any experiments to determine the circum- 
stances under which these drops are suspended. Having been 
deeply engaged in the experimental study of the phenomena of 
the surface-tension of water and the effect of the scum formed 
by oil or other substances, it occurred to me that the comparative 
rarity of these floating drops would be explained if it could be 
shown that they required a pure surface, a surface free from 
scum of any kind. For, owing to the high surface-tension of 
pure water, its surface is rarely free from scum. The surface of 
stagnant water is practically never free except when the scum is 
driven off by wind. But almost any disturbance in the water, 
such as the motion of a point of a stick round and round in the 
water, or water splashed on the surface, will serve to drive back 
the scum for a certain distance. This may be shown by scatter- 
ing some flowers of sulphur on the surface. This powder is 
insoluble and produces no scum, and hence it serves admirably 
to show the motion of the surface and whatever scum there may 
be upon it. If when the surface is s> dusted a splash be made 
by a stick so as to throw drops on to the sulphured surface, at 
the first splash no floating drops are produced ; but after two or 
three splashes in rapid succession it will be seen that the ‘sul- 
phured scum has been driven back by the falling water, leaving 
a patch of clear surface, and on this drops will float in large 
numbers and of all sizes. These drops are entirely confined to 
that portion of the surface which is clear. The drops, either by 
their initial motion or by the current of air, glide rapidly over 
the surface from the point at which they are formed. When, 
however, they reach the edge of the scum they disappear, 
apparently somewhat gradually. I have this summer made the 
experiment on several ponds and on various days, and I have 
never found any difference. Any scum, however transparent, 
prevented the drops, and they always floated in large numbers 
when the scum was driven back in the manner described, by the 
wind or any other way. This result points to the conclusion 
that whatever may be the cause of this suspension, it depends 
only on the surface of the water being pure, and not at all on 
the temperature or condition of the air.—On the mean intensity 
of light that has passed through absorbing media, by James 
Bottomley, D.Sc., F.C.S.—Note on the colour relations of 
nickel, cobalt, and copper, by James Bottomley, D.Sc., F.C.S. 
VIENNA 
Imperial:Academy of Sciences, October 13.—V. Burgin 
the chair.—The following papers were read :—A. v. Liebenberg, 
experiments on the part of lime in germination.—E. Weiss, 
computation of the elements and ephemeris of Barnard’s comet. 
—E. Briicke, on some consequences of the Young-Helmholtz 
theory.—T. W. Briihl, on the connection between the optic and 
thermic properties of liquid organic bodies. 
PARIS 
Academy of Sciences, October 17.—M. Wurtz in the chair. 
—The Secretary presented the instructions formulated by the In- 
ternational Conference for Observation of the Transit of Venus. 
—Crystalline sulphurated copper (cufréine), formed at expense 
of old coins, apart from thermal springs, at Flines-les-Roches, 
Departement du Nord, by M. Daubrée.—Observations of the 
comet 4 1881 (Tebbutt-Gould-Cruls) at Paris Observatory, by 
M. Bigourdan.—On a remarkable configuration of circles in 
space, by M. Stephanos.—On Fuchsian functions, by M. Poincaré. 
—On an experimental peculiarity relative to the equipotential 
law of Nobili’s rings, by M. Guébhard. He has studied, under 
strong light, the trajectories of minute bubbles between electrodes 
in badly-conducting liquids; these are quite determinate and 
independent of gravity, and (friction and agitation of the liquid 
apart) seem to represent lines of force of the electric flow. 
With variously formed electrodes he has repeated Antolik’s and 
Mach’s experiments made with static discharge ; and profiting 
by certain effects of polarisation, and counter-currents arising on 
quick reversal of the principal current, has obtained a fixed 
trace of the lines of flow.—Theory of a rapid vessel, by 
M. Pictet.—On the currents generated by atmospheric elec- 
tricity and earth-currents, by M. Landerer. At Tortosa he 
stretched a wire between the roofs of two houses in a direction 
making a small angle with the magnetic meridian, and connected 
it with the water-pipes. The currents ‘generated are variously 
due to condensation of aqueous vapour, to lightning-discharges, 
to action of wind, and to earth-currents. The first two and the 
fourth affect a telephone in the circuit, but not the third (these, 
however, as well as the second and fourth, deflect a galvano- 
meter). The earth-currents are distinguished from atmospheric 
currents by their regularity and continuity during pretty long 
intervals. Variation of the earth-current is a sign of change 
of weather.—Action of sulphur on alkaline sulphides in very 
dilute solution, by M. Filhol. In such action on dilute solutions 
of monosulphide of sodium a polysulphide is formed, without 
notable production of hyposulphite, and it seems as though the 
original monosulphide has subsisted, spite of the dilution. But 
more probably it is decomposed and reconstituted.—On a 
new series of bases derived from morphine, by M. Grimaux. 
—On a new alkaloid of quinquinas, by M. Arnaud. The 
formula adopted for cinctonamine (this new alkaloid) is 
