NATURE 
[FEBRUARY 24, 1923 

274 
Societies and Academies, 
Lonpon. : 
Royal Society, February 15.—E. R. Speyer: 
Researches upon the Larch Chermes (Cnaphalodes 
strobilobius, Kalt.), and their bearing upon the evolu- 
tion of the Chermesine in general. Alternation of 
form is the normal course of biological development 
in all Chermesine, but it breaks down in Cnaphalopes 
strobilobius, Kalt. The Progrediens type of all 
Chermesinz is potentially a winged form, and is 
not a true dimorphism of the Sistens type. The 
Sexuales are different morphologically from all other 
generations and are probably a new production in 
evolution. Species which are purely parthenogenetic 
have ceased to develop from an evolutionary point 
of view, and show the probable course of evolution 
in the various genera. Migration from one species 
of conifer to another is responsible for a duplication 
in the series of form-alternating, parthenogenetic 
generations ; the series upon one conifer has become 
morphologically different from that on the other 
through the action of Natural Selection in two 
different environments. In existing species with 
two host-plants, that portion of the cycle which now 
takes place upon the definitive host-plant has arisen 
through a stimulus given by a recent return to 
sexuality, this accounting for the linking up of the 
two cycles and a duplication of the series of partheno- 
genetic generations.—G. V. Anrep: The irradiation 
of conditioned reflexes. Experiments were performed 
with tactile conditioned reflexes, the parotid gland 
being taken as the effector organ. The tactile 
reflexes established on one side of the animal irradiate 
without a measurable decrement into the other side 
of the animal. The conditioned inhibition is in 
broad limits a cruder form of inhibition than the 
differential inhibition. The irradiation of the condi- 
tioned inhibition follows in the main the rules estab- 
lished for the irradiation of the differential inhibition 
and that of the reflex itself. The short trace reflexes 
take an intermediate position between the simul- 
taneous and the long trace reflexes.—M. Dixon and 
H. E. Tunnicliffe: The oxidation of reduced gluta- 
thione and other sulphydryl compounds. The reduc- 
tion of methylene blue by the sulphydryl compounds, 
reduced glutathione, cystein, and thioglycollic acid, 
is an autocatalytic reaction. The active agent 
producing this catalysis is the disulphide form 
R.S.S.R. The disulphide compounds also catalyse 
the oxidation of the sulphydryl compounds by 
atmospheric oxygen. The form of the reaction 
curves is not autocatalytic. The reaction velocity 
in the cases of glutathione and cystein shows a sharp 
optimum at a pH of 7-4. Thioglycollic acid does 
not show this. The bearing of these results on the 
conception of the function of glutathione and related 
compounds in tissue oxidation processes is discussed. 
—J. C. Bramwell, R. J. S. McDowall, and B. A. 
McSwiney: The variation of arterial elasticity with 
blood pressure in man. A method is described by 
which the extensibility of an artery in living man 
may be measured at all internal pressures up to the 
diastolic pressure. As in the case of an isolated 
artery, the extensibility decreases as the internal 
pressure is increased.—L. J. Harris: On the existence 
of an unidentified sulphur grouping in the protein 
molecule. Pt. I—On the denaturation of proteins. 
Pt. I1.—On the estimation of cystine in certain 
proteins. The conditions under which the grouping 
reactive to nitroprusside is liberated from ovalbumin 
and other proteins, and of its survival in the proteose, 
peptone, and polypeptide molecule, were examined. 
NO. 2782, VOL. 111] 


The nitroprusside reaction, attributed by Arnold to 
cystein, may be due to the presence of a grouping 
of the thiopeptide type. 
cystine in proteins by a new method indicates that 
whereas in serum albumen the cystine accounts for 
89 per cent. of the total sulphur content, in oval- 
bumin 86 per cent. of the sulphur still remains to be 
accounted for.—N. B. Laughton: Reflex contractions 
of the cruralis muscle in the decerebrate and spinal 
frog. In the decerebrate frog there was a prolonged 
tonic after-effect in the contraction of the cruralis 
muscle on reflex stimulation of the ipsilateral sciatic 
nerve. No such tonic effect was observed in the 
cruralis muscle of the spinal preparation. A shorter 
latent period and a more rapid increment of height 
were marked in the spinal preparations. During 
spinal shock the height of the reflex contraction in 
the spinal frog is not maximal. In half the experi- 
ments the height of the myogram was greater in 
the decerebrate than in the spinal preparations. 
British Mycological Society, January 20.—H. Wor- 
mald: Crown gall on nursery stock. Résumé of 
crown gall investigations and account of crown gall 
on apple stock in this country.—Miss W. Ridler: The 
fungus present in Lunularia cruciata. The fungus is 
not constant in occurrence, but when it occurs, it is 
definitely localised. There is no evidence that the 
fungus has any effect on the production of sexual 
reproductive organs or gemmez or on the size of the 
plants. The association is regarded as harmless 
parasitism on the part of the fungus.—A. S. Horne: 
The systematic characters of closely allied strains of 
Fusarium were described. Spore shape, dimensions, 
and septations have proved exceedingly variable and 
of less relative value in classification than occurrence 
of sclerotia, chlamydospores, colouring principles, re- 
lation to active hydrogen, etc. ‘‘ Sectoring’”’ often 
occurs in culture and has resulted in increase in the 
number of strains from 6 to about 14.—W. Brown: 
Experiments on growth rate and cultural factors of the 
same species of Fusarium. The amount of “ staling ” 
varied in different strains. Practically any cultural 
characteristic can be developed in any one strain by 
choosing suitably the composition of the various 
constituents of a synthetic medium.—J. Ramsbottom : 
Berkeley and Broome: An account of the way in 
which these two mycologists became interested in the 
study of fungi and associated together, as shown by 
their correspondence in the British Museum (Natural 
History). 
Geological Society, February 7.—Prof. A. C. 
Seward, president, in the chair.—G. Vibert Douglas: 
Geological results of the Shackleton-Rowett (Quest) 
expedition. The more detailed work commenced in 
South Georgia, which lies 900 miles east of Cape 
Horn and is roo miles long by 20 miles in width. 
It is an upland dissected by glacial action. The 
glaciers in general show signs of withdrawal. The 
island consists of sedimentary rocks and, at the south- 
eastern end, igneous rocks. The sediments may 
represent two periods of deposition, divided by an 
unconformity. The rocks all show signs of meta- 
morphism, and the strike of the folds and lamellze 
of the phyllites indicate that the pressure came 
either from the south-south-west or from the north- 
north-east. Elephant Island is situated in the 
Powell group of the South Shetlands and is an ice- 
covered plateau rising to 1200-1500 feet above sea- 
level. The Tristan da Cunha Group, 1500 miles 
west of the Cape of Good Hope, are of volcanic origin. 
Gough Island, more than 200 miles south of the 
Tristan da Cunha Group, is 8 miles long by 3 miles 
Gravimetric estimation of 
re a a ee 
—— — 
