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which affects the proportion of all the solids of blood as compared with
the water. The fatty acids appear also to be partly in combination with
cholesterin, forming cholesterin-esters, of which two have been separated
by Hiirthle ^ in a crystalline form, namely, the olein and palmitin com-
pounds, to the extent in horse serum of 0-08 and 0-06 per cent, respec-
tively. Hiirthle further found that in the dog they were increased
during inanition. The amount of cholesterin in serum or plasma is
stated by Hoppe-Seyler to be about 0-05 gr. per 100 c.c. blood,^ and is
probably mainly in the form of the fatty acid combinations just referred
to, and not, as was formerly supposed, in the free condition (Hiirthle).

Lipochrome. — -The yellow-colouring matter of serum is a lipochrome
soluble in amylic and also in ethylic alcohol, but insoluble in turpentine.
Its absorption spectrum shows two ill-defined bands,^ one at the F and
the other between the F and G- Frauenhofer lines (Plate ill.. Fig.
24). It resembles the lutein of Klihne.

Lactic acid. — The presence of sarcolactic acid as a regular con-
stituent of normal blood plasma has been affirmed (0 '01 7-0 -05 4 per cent,
in dogs).^ Salomon could only find it in blood from the dead body, not
in that drawn during life,^*^ but Irisawa confirms its existence in fresh
blood (dog), and states that it is present to some extent in the cor-
puscles as well as in the plasma.^^ It is increased in blood which has

^ Pavy, "On Certain Points connected with Diabetes"; Seegen, Wien. mecl. fFchnschr.,
1886, S. 1561 and 1595.

^ Rohrig, Abhandl. d. math.-phys. CI. d. Tc. Sachs. Gesellsch. d. JVissenscli., 1874, S. 1,
and Arh. a. d. j^hysiol. Anst. zio Leiq)zig.

^ Hojjpe-Seyler, Ztschr. f. physiol. C'hem., Strassbui'g, Bd. viii. S. 503.

■* Bornstein, Diss.. Breslau, 1887.

5 Arch.f. d. ges. Physiol., Bonn, 1889, Bd. xlvi. S. 383.

^ Ztschr. f. physiol. C'hem., vStrassburg, lS9o, Bd. xxi. S. 331.

"^ Med. Chem. Untersuch., Berlin, 1866, S. 145.

^ Krnkenberg, Sitzimgsh. d. Jenaisch. Gesellsch. f. Med. u. Nahiriv. ,1885, Siipiil. Bd. xix. S. 25.

8 Gaglio (with Drechsel), Arch.f. Physiol., Leipzig, 1886, S. 400; Spire, Ztschr. f.
physiol. Chem., Strassburg, 1887, Bd. i. S. 110 ; Berlinerblau (with Nencki), Arch. f.
exper. Path. u. Pharmacol., Leipzig, 1887, Bd. xxiii. S. 333.
" Firchow's Archiv, 1888, Bd. cxiii. S. 356.
^^ Ztschr. f. p)hysiol. Chem., Strassburg, 1893, Bd. xvii. S. 340.


been perfused through the still living kidneys or lungs, or through the
muscles of the lower liinb, especially if inosit or glycogen or dextrose
be added to the blood used for perfusion (Gaglio, Berlinerblau). It is
also increased by intravenous injection of dextrose in blood circulating
normally through the body. It appears to enter into combination with
sodium hydrate, driving out Q^O.j}

Non-proteid nitrogenous constituents of plasma. — The most im-
portant of these are urea^ (0-02-0-05 per cent.), kreatin, kreatinine,^
and uric acid,* and occasionally hippuric acid.^ Xanthine and hypo-
xanthine are stated to be also present.^ Grehant and Quinquand found
the amount of urea in blood drawn from the splenic, portal, and hepatic
veins to be shghtly greater than in that taken from the carotid.^
Lecithin occurs in small amount in plasma.^ According to Marino-
Zucco, neurine and glycero-phosphoric acid are also present in traces in
the free state. There has also been described as a constant constituent,
jecorin^ — a substance which reduces Fehhng's solution, but is soluble
in ether and is not fermentable. It is stated to occur in considerably
larger amount in venous than in arterial blood.^°

Ferments. — Three ferments have been described as occurring in blood,
namely —

1. A diastatic ferment, producing the conversion of amyloids to sugar.

2. A glycolytic ferment, producing the disappearance of sugar.

3. A fat-splitting ferment (lipase).^^

4. A fibrin ferment (thrombin), or its precursor (prothrombin), pro-
ducing the formation of fibrin from fibrinogen. The last will be con-
sidered in connection with coagulation.

Diastatic action. — A ferment action, converting starch into dextrin
and maltose, and ultimately into dextrose, has been obtained with
blood and lymph by Eohmann ^^ and Bial,^^ and also by Hamburger ,i* by

1 Vauglian Harley, Arch. f. PMjsioL, Leipzig, 1894, S. 451.

2 Simon, Arch. f. Anat. u. Phijsiol., Leipzig, 1841, S. 454 ; I. Munk, Arch. f. d. ges.
Physiol., Bonn, 1875, Bd. xi. S. 105 ; Schroder, Arch. f. exper. Path. u. Pharmakol.,
Leipzig, 1882, Bd. xv. S. 364 ; and 1885, Bd. xix. S. 373. Picard {Jov.rn. cle Vanat. et
physiol. etc., Paris, 1881, p. 530) found the percentage of urea rather higher than this in
the dog (0-09 to 0-13).

3 Verdeil and Marcet found both kreatin and kreatinine {Journ. de pharm. et chim.,
Paris, 1851, tome xx. p. 89) ; Voit {Ztschr. f. Biol., Miinchen, 1868, S. 93) could find no
kreatinine ; but Colls (Journ. Physiol., Cambridge and London, 1896, vol. xx. p. 107)
obtained a small but definite quantity.

4 Scherer and Strecker, quoted by Hoppe-Seyler ("Physiol. Chem."); Garrod, 3'Ied.-
Chir. Trans., London, 1848, vol. xxxv. p. 83, and 1854, vol. xxxvii. p. 49. See also
"Nature and Treatment of Gout," 1861 ; Abeles, Med. Jahrb., Wien, 1887, S. 479. On
the other hand, v. Jaksch {Ztschr. f. Heilk., 1890, Bd. xi. S. 415) could find no uric
acid in the blood of healthy individuals (nine cases).

5 Verdeil and Goldfuss, Compt. rend. Soc. de Uol. , Paris, 1 850, tome ii. p. 79. Meissner and
Shepard (" Untersuch. li. d. Ensteh. d. Hippurs.," Hannover, 1866) were unable to find it.

« Halliburton, "Chem. Physiol.," p. 251.

■^ Journ. de Vanat. et physiol. etc., Paris, 1884, p. 317.
8 Hoppc-Seyler, Mtd. Chem. Untersuch., Berlin, 1869, S. 551.

» Baldi, Arch. f. Physiol., Leipzig, 1887, Suppl. Heft, S. 100; Henriques, Ztschr. f.
physiol. Chem., Strassburg, Bd. xxiii. S. 244.

lojacobsen, Centralhl. f. Physiol., Leipzig u. Wien, 1892, S. 368.

^^ Hanriot, Compt. rend. Soc. de liol., Paris, 1896, p. 925.

12 Arch.f. d. ges. Physiol., Bonn, 1892, Bd. lii. S. 157.

13 /6i(^., 1892, Bd. iii. S. 137; and Bd. liii. S. 156; Rbhmann and ^laX, Arch. f.
d. ges. Physiol., Bonn, 1893, Bd. liv. S. 72 ; Bd. Iv. S. 469. According to Lepine and
Barral {Compt. rend. Acad. d. sc, Paris, 1893, tome cxiii., pp. 118, 729, 1014, and cxv.
]). 304) sugar may be formed in blood on standing, at the expense of added peptone, as
well as starch or glycogen ; but this was not confirmed by Bial.

^"lUd., 1895, Bd. Ix. S. 543.


mixing blood or serum with starch or glycogen solution, and keeping it
at body temperature. Eohmann has shown that the diastatic change may
occur in lymph within the vessels as well as in vitro. Cavazzani
obtained most effect in blood taken from the portal vein.^ Tscherevkoff"
finds that the diastatic ferment is precipitated by excess of alcohol, and
that its action is not destroyed by long standing under alcohol, nor by
sodium oxalate.^

Glycolytic action. — It was noticed by Bernard^ that the sugar of
blood diminished on standing in vitro. Pavy found that both the normal
sugar and added sugar diminishes in blood on standing.* In any case,
and without standing, it is difficult to recover the full amount from
blood or serum, apparently owing to the fact that, in coagulating the
proteids with a view to their removal, a part of the sugar is mechanically
carried down or retained by them;^ this fact may lead to very con-
siderable experimental errors.^ Allowing, however, for such errors, it
appears clear that there is some actual loss of sugar on standing both
in blood '^ and in lymph or chyle.^ According to Seegen, the glycolytic
action is active in the presence of chloroform, and is destroyed by a
temperature of more than 54° C, in these respects resembling an enzyme.
Lepine states that it is absent or diminished in activity in diabetes,^
whether the result of disease or operation (removal of pancreas), and
that a very active glycolysis occurs in perfusing blood through various
organs (kidney, lower limbs).^'^ Arthus, on the other hand, denies the
pre-existence of a glycolytic ferment in blood. He finds no glycolysis
in oxalated blood, and thinks it probable that the ferment is formed
from leucocytes during coagulation. ^^ Kraus finds that the glycolysis
which occurs in blood on standing is accompanied by a splitting off of
CO2, and is probably due therefore to oxidation.^^

Proteids of plasma. — The proteids of plasma are —

1. One or more closely allied albumins (serum albumins).

2. Two globulins, termed respectively serum globulin and fibrmogen.

3. A nucleo-proteid or nucleo-proteids.

Blood contains normally neither albumose nor peptones.^^ All the
proteids are completely precipitated by saturating plasma with ammo-

^ Arcli. 'per U sc. med., Torino, 1893, vol. xvii. p. 105.

^ Arch. dej)hysiol. norm, etpath., Paris, 1895, p. 628.

^ Compt. rend. Acad. d. sc, Paris, 1876, p. 1406.

^ Proc. Roy. Soc. London, 1877, vol. xxvi. p. 346 ; and 1879, vol. xxvii. p. 520. See
also "Physiol, of Carbohydrates," pp. 171-179.

^ Rohmann, Centralbl. f. Physiol., Liepzig 11. AVien, 1890, No. 1 ; V. Harley, Journ.
Physiol., Cambridge and London, 1891, vol. xii. p. 391 ; Pavy, Brit. Med. Journ., London,
1896, vol. i..p. 453.

f' Schenck, Arch. f. d. ges. Physiol., Bonn, 1890, Bd. xlvi. S. 607; 1891, Bd. xlvii.
S. 621. For a method whereby such errors may be largely avoided see E. Waymouth
Raid, Journ. Physiol., Cambridge and London, 1896, vol. xx. p. 316.

"^ Rohmann, loc. cit. ; Harley, loc. cit. ; Seegen, IVien. Min. JFchnschr., 1892, Nos. 14
and 15.

^ Lupine, C'ompt. rend. Acad. d. sc, Paris, 1890, tome ex. p. 742 ; Lepine and Barral,
ibid., 1890, tome ex. p. 134 ; ibid., 1891, tome cxii. pp. 411, 604, 1185, 1414 ; and
tome cxiii. p. 118.

^ Lepine and Metroz, ibid., 1893, tome cxvii. p. 154.

^^ Lepine and Barral, loc cit.

" Arch, de p)hysiol. norm, et path., Paris, 1892, p. 337 ; Compt. rend. Acad. d. sc,
Paris, 1892, tome cxiv. p. 605.

^^ Ztschr. f. Iclin. Med., Berlin, 1892, Bd. xxi. S. 315. See also Rohmann and Spitzer,
Ber. d. deutsch. chem. Gesellsch., Berlin, Bd. xxviii. ; and Spitzer, Arch. f. d. ges. Physiol.,
Bonn, 1895, Bd. Ix.

^^ Halliburton and Colls, Journ. Path, and Bacterial., Edin. and London, 1895, p. 295.
VOL. I. — II



nium sulphate. The globulins and nucleo-proteids are completel}^ pre-
cipitated by half-saturation with ammonium sulphate, or by complete
saturation with magnesium sulphate ; whilst fibrinogen is precipitated
by half -saturating plasma with chloride of sodium (probably some nucleo-
proteid is carried down with it). Upon these differences of solubility in
solutions of neutral salts the separation of the blood-proteids one from
another depends.

The proportion of globulin to albumin ^^ ^^^ is known as tbe " proteid

albumin ^

quotient " ; it varies in different animals and in tlie same species of animal

imder different conditions. ^ For the same individual it is almost constant in

the blood serum, lymph, and serous transudations, although the absolute

amount of proteid in these may vary greatly.^

The annexed table ^ shows the total and relative amounts of the proteids
in the serum of different animals. The numbers are taken from different
sources ; the first four from Hanunarsten.^

They are obtained — (a) the total proteids, by weighing the alcohol
precipitate ; (&) the globulin, by separating off the magnesium sulphate
precipitate, re-dissolving this and weighing its alcohol precipitate: (c) the
albumins, by taking the difference between these two results. (&) includes,
besides serum globulm, a globulin formed from fibrinogen in coagulation, and
also the nucleo-proteids of plasma, but both of these are in very small amount.

(a) Total Proteids

(6) Globulins

(c) Albumins

per Cent.

per Cent.

per Cent.









Ox .












Hen .




















Fro£( .












Eel .








The most noteworthy feature shown in these figures is the relatively
small amount of albumins present in the serum of cold-blooded animals
as compared with the globulins. It has been stated that the albumins
proportionately diminish in starved animals,^ but other investigators
have failed to confirm this conclusion.^

^ Compare Frassineto, Arch. ital. de biol., Turin, 1895, vol. xxiv. p. 457 ; Paulesco,
Arch, dcphyniol. norm, ct 2Mth., Paris, 1897, p. 21 ; W. Engel, Arch. f. Hyg., Mtinchcn
u. Leipzig (4), Bd. xxviii. S. 334.

~ Salvioli, Arch. f. Physiol., Leipzig, 1881, S. 269; Hoffmann, Arch. f. exper. Path. u.
Pharmakol., Leipzig, 1882, Bd. xvi. S. 133.

^ Halliburton, Journ. Physiol., Cambridge and London, 1878, vol. vii. p. 321.

■• Arch.f. d. ges. Physiol., Bonn, 1878, Bd. xvii. S. 413.

" Tiegel, ibid.. 1880, Bd. xxiii. S. 278 ; Burckhardt, Arch. f. expcr. Path. n. Pharraalcol.,
Leipzig, 188.3, Bd. xvi. S. 322.

"Salvioli, Arch. f. Physiol., Leipzig, 1881, S. 269; Howell, John Hopldns Univ.
Stud. liol. lab., Baltimore, vol. iii. p. 49; Rubbrecht, Trav. du lab. de L. Fredericq
tome V. ]i. 121.


Albumins of blood ijlasma. — The albumins of plasma are also found
in the serum after coagulation of blood, and hence they have been
termed serum albumins. They remain in plasma or serum after half-
saturating it with ammonium sulphate, i.e. by mixing it with an equal
amount of saturated ammonium sulphate solution, or after entirely
saturating it with magnesium sulphate.

The precipitated globulins and nucleo-proteid are removed by filtra-
tion, and the filtrate dialysed to remove the salts. The solution which
remains contains only the albumins ; they can be precipitated from it by
saturation with ammonium sulphate or by sodio-magnesium sulphate.
According to Giirber, they can be obtained in a crystalline form by
adding ammonium sulphate just sufficient to produce precipitation and
allowing the fluid to stand exposed to the air.^

The material obtained in these ways constitutes what has usually
been called serum albumin (serine), but, as Halliburton has shown,^ it is
really a mixture of three separate albumins, which he has termed
respectively a, |3, 7. These differ from one another in their temperature
of heat coagulation ; a-albumin coagulates at 72°-75° C. ; /S-albumin at
77°-78° C. ; and 7-albumin at 83°-86° C. In the plasma of horse, ox,
and sheep blood, a-albumin is absent, but the other two are present ; in
man, and all other mammals and birds investigated by Halliburton, all
three were present ; but in reptiles, amphibia, and fishes investigated,
a-albumin was usually the only one found.^

The crystals of serum albumin which were obtained by Giirber from the
serum of horse's blood were hexagonal prisms with one pyramidal end,
and were doubly refracting ; some of them were as much as 1 cm. long.
Their elementary composition was C, 53'1 ; H, 7*1; JST, 1.5-9; S, 1-9,
0"22 ; and ash, 0*22 per cent. Dissolved in water and the excess of
ammonium sulphate removed by dialysis, the solution had a heat coagulation
temperature of 51" to 53°, and a specific rotation for yellow light of -61°.^

The globulins of blood 23lasma. — The globulins of blood plasma con-
sist of serum globulin and fibrinogen. Serum globulin (paraglobulin,
Klihne ; fibrino -plastic substance, A. Schmidt) has a heat coagulation
temperature of 75° C, which is almost constant in all animals in
which it has been examined. The amount to which it is contained
in plasma is represented by the figures in the second column of the
table on p. 162. It will be seen from this, that in man it constitutes about
three parts per cent, of the total serum. It is precipitated from serum by
half-saturation with ammonium sulphate,^ and also by complete saturation
with magnesium sulphate, sodium chloride, and some other neutral salts
which do not precipitate the albumins ; also, but less completely, by dilut-
ing the serum with water (fifteen times) and passing CO2 through it, or by

1 Sitzimgsb. d. phys.-med. Gesellsch. zu Wilrzhihrg, 1894, S. 143.

^ Journ. Physiol., Cambridge and London, vol. v. p. 152.

•^ In the slider ten'apin (Howell, John Hopkins Univ. Stud. hiol. lah., Baltimore, vol.
iii. p. 49) the albumin present is apparently of the /S variety, coagulating at 77° to 80°,
and in the eel and dog-fish this variety was also found by Halliburton (/mtra. Physiol.,
Cambridge and London, vol. vii. p. 320).

''Michel (with Giirber), Verhandl. d. phys.-med. Gesellsch. zu JVilrzburg, 1895, N. ¥.,
Bd. xxix. No. 3.

^ Kauder {Arch. f. exper. Path. it. Pharmakol., Leipzig, 1886, Bd. xx. S. 411) found
that solutions of ammonium sulphate stronger than 24 per cent, completely precipitated
serum globulin; above 33 '5 per cent, some of the serum albumin also comes down. A
half-saturated solution contains about 26 per cent.


diluting with water and neutralising it with dilute acetic acid (m excess
of which it easily dissolves). Like other globulins, it requires the
presence of a certain amount of salts, or weak alkali, to be dissolved in
water ; it is therefore precipitated by dialysis or by sufficient dilution
of its solutions in salts or in serum, even without the addition of an

Fibrinogen. — This is the substance to which the plasma of the blood
especially owes its property of so-called spontaneous coagulability ; which
led to the term " coagulable lymph " being applied to it by older writers.^
It is precipitated from plasma along with serum globulin, by saturation
with magnesium sulphate or sodium chloride ; the precipitation of
mixed globulins so obtained (the plasmine of Denis) forms a coagulable
liquid, on dissolving it in a more dilute solution of salt. Fibrinogen is
entirely precipitated from plasma, or any other fluid containing it, by
half-saturation with sodium chloride ; ^ it can be re-dissolved in water
with the aid of the salt adhering to it, reprecipitated by half-saturation,
and so on until it is obtained in a condition which may be regarded as
approaching purity. But in contact with the salt solution it gradually
loses its solubihty, and every time that it is precipitated less of the
precipitate redissolves on adding water ; the material which forms and
which remains undissolved in the dilute solution of salt resembles
fibrin in many physical and chemical characters, but is not similarly
rapidly swollen by dilute acids ; it may be termed para-jibrinogen or
pseuclo-Jibrin. Fibrinogen dissolves also in dilute alkah, even in the
absence of neutral salts ; its alkaline solutions are clear, but its solutions
in neutral salt solutions are opalescent. It is precipitated from the
solution in weak alkali by careful neutralisation with acetic acid, and from
solutions in neutral salt solutions by slightly acidulating with the same
acid, but it is readily soluble in excess of the acid. The temperature of
heat coagulation of fibrinogen in salt solution is between 52° and 55° ; ^
but the whole of the dissolved proteid is not thrown down at this
temperature ; a small amount remains in solution, and is not coagulated
until the temperature of 65° C. is attained. According to Hammarsten,^
this is due to the splitting of the fibrinogen, under the influence of
heat, into coagulated fibrinogen and a globulin, which is coagulated at
the higher temperature. If fibrinogen which has been obtained from
blood plasma by the above method of half-saturation with NaCl, and
purified by repeated re-solution and re-precipitation with acetic acid, be
dissolved in water rendered faintly alkaline by NaHO, it gives a
coagulum-like precipitate (if sufficiently concentrated) a short time after
the addition of a lime salt. The coagulum resembles fibrin in many
respects, but, according to Hammarsten, it is not true fibrin, but a
combmation of fibrinogen with lime.^

1 HouLston, Diss. Med. Inaug., " de Inflammatione," pp. 11, 12, 14, Liigd. Bat., 1767.
See Hewson's Works, Introduction, p. xxxvii, edited by G. Gulliver, London, printed for
the Sydenham Society, 1846.

^ Hammarsten, Arch. f. d. ges. Physiol., Bonn, 1879, Bd. xix. S. 563.

3 Hammarsten, ibid., 1880, Bd. xxii. S. 431.

•^ Ibid., 1879, Bd. xix. S. 563.

''Hammarsten. Ztschr. f. physiol. Chem., Strassburg, 1896, Bd. xxii. S. 333. It is
unnecessary to add any ferment or nucleo-proteid to the solution to produce the result, but
there is no doubt that nucleo-proteid may be jiresent along Avith the fibrinogen. It was
shown by Lilienfeld {ZLschr. f. i^Jiysiol. Chem., Strassburg, 1895, Bd. xx. S. 89) that
filninogen prepared liy Hammarsten's method contains nuclein ; from this he inferred that
it is a nucleo-proteid, and not a globulin. But the amount of nuclein present is not sufficient


As just stated, fibrinogen is precipitated from plasma, and from
its solutions in neutral salt solution, or dilute alkalies, by the addition of
dilute acetic acid, even in slight excess. This precipitate has been
termed " thrombosin " by Lilienfeld,^ who regards it as due to a splitting
of the fibrinogen under the influence of the acid into this substance and
an albumose, but it has not been shown that it possesses any properties
differing from fibrinogen."^

From what has been stated, it will be seen that it is improbable that the
material which is obtained from plasma, under the name of fibrinogen, is a
simple substance. It is probably either a mixture, or a loose combination, of
at least three substances, namely —

1. Fibrinogen proper, coagulating at 56° C.

2. The globulin described by Hammarsten, and .termed fihrino-glohulin,
coagulating at 65° C.

3. A nudeoproteicl.

The nucho-proteid of plasma. — Beyond the fact of its presence, and
that it appears to be one of the esseirtial factors in the formation of
fibrin, very little is known regarding the nucleo-proteid of blood plasma.
It is doubtful if it exists in the plasma of circulating blood ; it is
thought by many that in this it is confined to the white corpuscles and
blood platelets — a very little being also present in the red corpuscles —
and that it is shed out by these as soon as the blood is drawn. The
reasons for this belief are —

1. White blood corpuscles and similar cells (lymph cells, thymus
cells, etc.) always contain a considerable amount of nucleo-proteid.

2. In plasma obtained by subsidence of the corpuscles there is most
nucleo-proteid in the lower layers, which contain most leucocytes ; and
least in the upper, which contain very few.

3. Fluids which collect in the serous cavities of the body (peri-
cardial fluid, hydrocele fluid, ascitic fluid) frequently corrtain no
leucocytes. When this is the case they are also devoid of nucleo-
proteid and of the property of spontaneous coagulability, although they
contain fibrinogen.

The nucleo-proteid is precipitated from oxalate plasma, by allowing
it to stand for twenty-four hours at 0° C. The addition of acetic acid
in slight excess also throws it down, but not in a pure form, for fibrin-
ogen is carried down alorrg with it. Its solutions are coagulated at 65° C. ;
at a temperature of 60° C, in presence of free alkali, it is split into
nuclein and a proteid. This is stated by Pekelharing to be a proteose,^
but its proteose character is denied by Martin.* Halliburton and Brodie
could also find no proteose in blood after the injection of nucleo-
albumin.^ In the presence of soluble salts of lime, it forms a

to justify this inference, and its presence is probably dne to the fact that some or all of
the nucleo-proteid present in the plasma is precipitated along with the fibrinogen, and
clings to it in the subsequent processes of purification (Schafer, Proe. Physiol. 80c. , Journ.
Physiol., Cambridge and London, 1895, p. xviii). See later, p. 172.

^ Loc. cit.

^ Schafer, Proc. Physiol. Sac, Journ. Physiol., Cambridge and London, 1895, vol. xvii.
p. XX ; Hammarsten, Ztschr. f.jyhysiol. Chem., Strassburg, Bd. xxii. S. 384 ; Cramer, ibid.,

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