Marcu 4, 1897] 
NATURE 
429 
Laurent had proved, in 1892, that soil which contains both 
alge and bacteria does assimilate free nitrogen from the 
atmosphere, but it was desirable to ascertain how far pure 
-algze, without bacteria, are endowed with the same capacity. 
This work was undertaken by the author, under the guidance of 
A. Koch. The result is that pure cultures of Cys¢ococcus and, 
very probably also, of Stzchococcus do not assimilate free 
nitrogen. On the contrary, a soil which contains both alge 
and bacteria can be enriched to a considerable extent with 
nitrogen absorbed from the atmosphere. The algze aid, in such 
cases, the bacteria in their work of assimilation, as they enrich 
the soil with hydrocarbons, which are required for the growth of 
the former. A sort of symbiosis thus takes place between the 
alge and the bacteria; but, of course, it would be premature 
to maintain that no algze whatever can absorb free nitrogen. 
—Materials for the Flora of the Turkestan Highlands: the 
Basin of the Zerafshan, by V. Komaroff. This is a detailed 
work in which a list of 362 species is given, and is preceded by 
a general sketch of the vegetation of the valley of the Zerafshan 
{this latter has already been referred to in a previous issue). 
—Physiological researches into the growth of elementary 
organisms, by K. A. Stameroff. The influence of light on the 
speed of growth of hyphe of JMzucor, Pentcéllum, and Sapro- 
Jegnia, of rhyzoids of Marchantia polymorpha, and of the pollen 
of various plants, were studied, and complete results, both posi- 
tive and negative, were obtained.—An addition to the lists of 
the flora of the Government of Novgorod, by V. Komaroff; and 
-on the same flora, by A. Kolmovsky and A. Antonoff. 
Vol. xxvi. 2, 1896: Section of Zoology and Physiology.— 
‘Some observations on the embryonic development of Meonzysis 
wulgarts, var. Baltica, by Jul. Wagner, with five plates, fully 
summed up by the author in German.—Observations on sperma- 
togenesis with spiders, by the same author, with two plates, and 
also fully summed up in German.—Note on the influence of a 
permanent current on the muscle irritated through the nerve, by 
A. D. Grigorieff. 
SOCIETIES AND ACADEMIES. 
LonpDon. ; 
Royal Society, February 4.—‘‘On the Condition in which 
ats are absorbed from the Intestine.” By B. Moore and D. P. 
Rockwood. Communicated by Prof. E. A. Schafer, F.R.S. 
In these experiments the solubility of the mixed fatty acids of 
-beef suet, mutton suet, and Jard in the bile of ox, pig and 
-dog was determined at body itemperature, and found to vary 
‘between 1 and 7 percent. That the greater part of the fatty 
_acids is zo¢ dissolved as soap is shown by the ready solubility in 
ether of the precipitate thrown down on cooling, and the ease 
swith which it saponifies with sodium carbonate. 
Undoubtedly a small portion of the fatty acids added com- 
‘bines with the alkali of the bile to form soaps, for the reaction, 
which is at first alkaline to litmus, changes afterwards, becoming 
«strongly acid. The solubility of the mixed fatty acids in bile is 
only in part due to the bile salts, fora more concentrated solu- 
tion of these than bile itself did not dissolve nearly so large an 
-amount of fatty acids. And, again, mere removal of the 
*< pseudo-mucin ” from bile greatly diminishes its solvent action 
-on fatty acids, although the ‘‘ pseudo-mucin” redissolved in 
-sodium carbonate has no solvent power. 
The contents of the intestine were removed in dogs during fat 
absorption and filtered. The filtrate decomposed and dissolved 
neutral fats at the temperature of the body. This effect is due 
*to the simultaneous action of pancreatic juice and bile. A 
‘similar result was obtained by acting on neutral fats with pan- 
-creas and bile, while pancreas alone decomposed the neutral fats 
‘into fatty acids, but did not dissolve them. 
The solubilities stated above are quite sufficient to account 
for the removal of all the fat of the food from the intestine as 
-dissolved fatty acid, since they exceed the concentrations found 
-in the intestine of other materials, such as sugars and albumoses, 
which are removed in solution. Other experiments, however, 
on the reaction of the intestine during fat absorption, lead the 
authors to think that all the fat is not absorbed as dissolved fatty 
-acids, but that these are replaced to a variable extent (in some 
sanimals to a very large extent or completely) by dissolved 
soaps. 
The reaction of the contents of the small intestine to litmus 
-during fat absorption ‘in the dog is atthe pylorus neutral, faintly 
NO. 1427, VOL. 55] 
acid or faintly alkaline ; from here onwards the acidity increases, 
reaches a maximum about the middle of the small intestine, and 
then becomes less acid, to change to alkaline at a point situated 
about three-fourths of the way along the intestine. The reaction 
to methyl-orange and phenolphthalein explains this; the con- 
tents are alkaline to methyl-orange from pylorus to cecum, and, 
equally completely, acid to phenolphthalein, showing that the 
acid reaction to litmus in the upper part is due to weak organic 
acids, while the alkaline reaction in the lower part is due to fixed 
alkali, accompanied by dissolved carbonic acid. The alkaline 
reaction to methyl-orange in the upper part, where it is acid to 
litmus and phenolphthalein, shows that in that part there is an 
excess of bases, above that quantity necessary to combine with 
all the inorganic acids, which are combined with weak organic 
acids (probably fatty acids). In the lower fourth or thereabouts, 
where the reaction is alkaline to litmus, there cannot be any 
fatty acids present in solution. Therefore any fat that is ab- 
sorbed as free fatty acid must be taken up from the upper three- 
fourths of the intestine, where the reaction is acid to litmus. 
In the white rat during fat absorption the contents of the 
small intestine is alkaline to litmus from pylorus to c2zecum, and 
is never acid for a greater distance than two or three inches 
below the pylorus ; in this animal, therefore, nearly all the fat 
must be absorbed in solution as soaps. 
February 11.—‘‘On the Regeneration of Nerves.” 
Robert Kennedy, M.A., B.Sc., M.D., Glasgow. 
January 7. 
The author gives the clinical histories of four cases 
of division of nerves, in which restoration of function 
had not occurred at periods varying from a few weeks up to 
eighteen months from the date of section. Secondary suture 
was performed, and the gense of pain commenced to return in 
from two to five days, and sensation speedily became perfect. 
Motion was not recovered till a late date. 
He concludes that this early return of function is due to re- 
By 
Received 
| stored conductivity of the divided nerves, and that the theories 
which have hitherto been advanced to account for return of 
sensation apart from reunion of the nerve, are inapplicable to 
cases in which eardy return of sensation occurs from suture, per- 
formed after the lapse of several months from the time of sec- 
tion. The tardy and imperfect return of motion is explained on 
the ground that the muscles have undergone great trophic 
change, as a result of long separation from their trophic centres. 
From the histological changes found in the portions removed 
at the operations, he concludes : 
(1) That there is no evidence of ascending degeneration of 
the kind described by Krause after interruption of a nerve. 
(2) That the old axis-cylinder and myeline sheath are de- 
stroyed in the peripheral segment, and in the ultimate portion of 
the central segment. 
(3) That young nerve fibres are developed in the peripheral 
segment, as well as in the end of the central segment, and that 
even while there is no connection between the two ends. 
(4) That these young nerve fibres originate within the old 
sheath of Schwann from the protoplasm and nucleus of the 
interannular segment, the new axis-cylinder being developed 
from the protoplasm, while the nuclei remain attached to the 
sides of the new fibres. 
(5) That so long asthe conductivity of the nerve is not re- 
established, the development of the young fibres proceeds only 
to a certain stage, which may be regarded as a resting stage, as 
the fibres after three and eighteen months respectively present 
identical characters. E 
(6) That cicatricial intercalary segments may contain young 
nerve fibres from end to end without re-establishment of func- 
tion, if the amount of cicatricial connective tissue in the mass is 
sufficient to prevent by its pressure the passage of impulses. 
February 18.—‘‘ Note to the Memoir, by Prof. Karl Pearson, 
F.R.S., on Spurious Correlation.” By Francis Galton, ER:S: 
Received January 4. : 
This note was intended to serve as a kind of appendix to the 
memoir of Prof. K. Pearson, the author believing that it might 
be useful in enabling others to realise the genesis of spurious 
correlation. It was important, though rather difficult, to do 
so, because the results arrived at in the memot, which are of 
serious interest to practical statisticians, have at first sight a 
somewhat paradoxical appearance. 
The diagrams which accompanied the paper show how a table 
of frequency of the various combinations of two independent 
and normal variables may be changed into one of A/C, B/C, 
