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processes. We furthermore showed that cerAMEBOID MOVEMENT, TISSUE FORMATION

tain phenomena of wound healing can be

imitated in this experimental ambocyteAND CONSISTENCY OF PROTOPLASM1

tissue and that the formation of giant cells 1. IN 1901 we found through testing by

which takes place in sensitive cells in contact direct means the consistency of the proto

with a foreign body represents an application plasm that in the blood cells of Limulus

of the same principle. Here we have to asameboid movement depends primarily upon

sume that the process of liquefaction may alternating changes in the consistency of the

proceed so far that two cells may flow toprotoplasm, a phase of liquefaction being fol

gether. We also pointed out that variations lowed by a phase of hardening. There may be

in the hydrogen ion content of the cells added to these changes in consistency changes under the influence of stimulation might exin surface tension. Subsequently we showed

plain these changes. in experiments in which we likewise tested

2. A continuation of these experiments in the consistency of the cells directly that the

Woods Hole last summer showed that in the consistency varies under different conditions,

blood cells of Limulus it is possible to produce that these variations correspond not only to

graded variations in the character of the the pseudopodial activity, but also to the

pseudopods and ameboid movements through agglutinability of the blood cells and to the

graded changes in the osmotic pressure in formation of tissue like structures from

the surrounding medium. Again we find corpreviously isolated cells,2, 8 that these changes respondence between the consistency of the due to stimulation explained the stereotropism protoplasm and the character of the pseudoof tissue cells, 2, 4 that they played a part in

pods and amæboid movement. A particularly the processes of inflammation, 1, 2 phagocyto

great fluidity of the protoplasm could be prosis, and thrombosis. 5, 6, 7, 8 More recent ob

duced through the use of a slightly hypotonic servations in 1919 showed that it is possible

solution of KCl. In this case the change in to vary greatly the character of the amceboid

consistency became so marked that it affected movements and that the changes in the ame

not only the ectoplasmic layer of the cell, boid movements correspond to the changes in but extended to the whole of the granulothe consistency of the protoplasm; these ob- plasm. There is reason to assume that these servations suggested that the taking up of changes are associated with the taking up of fluid from the surrounding fluid on the part fluid from the surrounding medium. Under of the cells is an important factor in these those conditions a very peculiar phenomenon

which we described previously, a circus move1 From the Department of Comparative Pathol.

ment of the whole cell exoplasm as well as of ogy, Washington University, and from the Marine Biological Laboratory, Woods Holl.

the granuloplasm, can be produced regularly. 1 Leo Loeb, Jour. Med. Research, 1902, VII., 145.

These movements, however, take place only if 3 Leo Loeb, Biological Bulletin, 1903, IV., 301,

the temperature of the surrounding fluid is 2 Leo Loeb, Virchow's Archiv., 1903, CLXXIII., sufficiently high. It does not occur in cello 35.

kept at a temperature of 10°. + Leo Loeb, Anatomical Record, 1912, VI.

3. Exposure of the blood cells to a tempera5 Leo Loeb, Virchow's Archiv, 1905, CLXXXV., ture of approximately 40°-42° for a short 160.

period of time produces in the periphery of 6 Leo Loeb, Hofmeister's Beitraege 2. Chem. Physiol. 4. Pathol., 1904, V., 191.

9 Leo Loeb, “The movements of the Amebocytes 7 Leo Loeb, Pflueger's Archiv, 1910, CXXXI., and the experimental production of amạbocyte 465.

(cellfibrin) tissue," Washington University Stud8 Leo Loeb, Biochem. Zeitschrift, 1910, XXIV, ies, Scientific Series, 1920, Volume VIII., 3. 478.

(Here a general discussion of the subject is given.) the blood cells the appearance of multiple it had been recorded, but a search has failed drops into which the granuloplasm moves sub- to reveal any published statement. sequently as it does into typical pseudopods. If 1/n is the proportion of twin births to Transition can be observed between these all births in a large population during any drops and the typical pseudopods.

period, then the proportion of triplet births It is also possible to produce experimentally during the same period is very near to 1/n?. in the amoebocytes structures which very The agreement of the data is often startling. closely resemble ova in which maturation Thus in 13,360,557 births in Prussia during membranes have formed. Jacques Loeb has the years 1826–1849 as recorded by Veit the formerly shown that this formation depends number of twin births is one in 89.1 and the upon a proces of cytolysis. In the blood cells number of triplet births one in (88.9). In these structures appear under conditions in 1,339,975 births in the United States registrawhich the cell has taken up fluid from the tion area in 19178 the number of twin births surrounding medium and the consistency of is one in 93.1 and the number of triplet births the protoplasm resembles that of a liquid. one in (93.0)2. All kinds of transition between these struc

From the statistical relations it would aptures, drop pseudopods and the typical tongue- pear that triplets are produced by the coinlike pseudopods can be found. These and cidence of two independent processes occurother observations very strongly suggest that ring with equal frequencies. One of these the formation of pseudopodia, the appearance

processes by itself gives rise to twins. This of drops at the surface of the cells and the

relation would apply to any mode of origin of formation of fertilization membranes are

multiple births or to different combinations related phenomena and that the latter two

of them provided that each followed the rule. conditions represent extremes in a process

The principle might be applied to the two which, when acting in medium intensity, leads

chief explanations of multiple births as

follows: to the formation of the typical pseudopodia.

1. Multiple Ovulation.-Normally a single 4. Through changes in the consistency of the protoplasm in the blood cells of Limulus

ovum is discharged from the ovaries. There

is some coordinating mechanism which preit is possible to imitate the structures corre

vents the ripening of other ova at the same sponding to different tissues. Especially did

time. Suppose that as a result of a purely we obtain in certain cases through an increase

intrinsic factor, once in n times an ovum in the consistency of the cells tissues which resembled those composed of ganglia and glia

appears which fails to respond to this mech

anism. The chance that two such extra ova cells. It may thus be possible to obtain indications as to some of the conditions which

will appear at the same time is once in a induce the cells of different tissues to assume

squared. Obviously this presupposes that the

failure to respond is due to independent different forms.


processes in the two ova. To put the case WASHINGTON UNIVERSITY

more concretely, suppose that the approach to

maturation of an ovum is accompanied by an THE RELATIVE NUMBERS OF TWINS AND internal secretion which acts upon other ova TRIPLETS

and keeps them from completing the process It may be of interest to call attention to a at the same time. The overwhelming majorsimple relation between the number of human twin and triplet births. The relation was

2 Veit, G., 1855, Monatsschrift für Geburtskunde noticed a number of years ago and I supposed

und Frauenkrankheiten, 6: 127.

3 Birth statistics for the birth registration area 1 Contribution from the Zoological Laboratory of of the United States, 1917, U. S. Bureau of the the University of Illinois, No. 172.

Census, Washington, 1919.

ity of the ova would be properly inhibited but occasionally an ovum would fail to respond because of some peculiarity in its organization. Suppose that such peculiarities are due to local factors appearing with a frequency of 1/n. Then the chance that two such independent local factors will act at the same time and thereby cause the simultaneous discharge of two supernumerary ova is 1/n2.

2. Monozygotic Twins and Triplets.-Normally a single embryonic area appears in the blastodermic vesicle and through some coordinating mechanism inhibits the formation of additional embryonic areas. Suppose that once in n cases a cell or group of cells acquires physiological independence as the result of an intrinsic factor and forms a second embryonic area. The chance that two such cells or groups of cells will arise at the same time is once in n squared if it is supposed as in the previous case that the two events are independent of each other.

In order that the stated numerical relations may ensue, the important consideration in either mode of origin of multiple births is the independence of the two events which give rise to triplets. If, in the fluctuations of the general physiological state of the mother, the condition is sometimes such as to result in twins and sometimes in triplets, it is hard to see why the “square" relation should exist. For instance if it is postulated that additional ova are stimulated to complete the maturation process as a result of an unusual amount of an internal secretion and that the number of extra ova depends on the quantity of the secretion there is no reason for expecting the observed relation between one extra and two extra embryos. This difficulty seems to apply to all general agents that may be postulated as acting upon the ovaries as a whole in the cases of multiple ovulation or upon the developing embryo as a whole in the case of monozygotic twins and triplets. If, however, each supernumerary ovum is due to an independent local action and such local actions have a certain average frequency the coincidence of two such actions would give the observed numerical relation of triplets to twins.

If the explanation as stated applies to the relation between triplet and twin births it is to be expected that it will apply to quadruplets as well. In that case the expected number of quadruplets is one in ns. Unfortunately the numbers are too small for a reliable conclusion. In the largest available collection of data, the one mentioned above, there are 36 quadruplets in 13,360,557 births or one in (71.9)3 which is somewhat greater than the expected number, one in (89.1).

As in other statistical relations the biological significance in the present instance can not be proved directly from the mass of data. When one considers the vicissitudes of fertilization, the chances of death of individual embryos, the demonstrated influence of the spermatozoon in certain cases of twinning and numerous other biological factors, to say nothing of faulty registration statistics, it is hard to believe that the simple numerical relation of triplets to twins can be more than the result of the combination of numerous and as yet unanalyzed forces. A knowledge of the fact may, however, aid in the analysis.




C. A. Browne, chairman
Fred. J. Bates, secretary

(Concluded) The sugar industry of Peru: CHAS. A. GAMBLE.

Electric oven for rapid moisture tests: G. L. SPENCER. This oven (patented August 3, 1920) is a convenient arrangement for passing a rapid current of heated air through a sample. The air is drawn over a heating element, composed of a spiraled nichrome wire coiled around a suitable core, and thence through the sample contained in a capsule, fitted with a gauze or metal filter-cloth bottom. The temperature of the air is controlled by a rheostat. Any substance through which a current of hot air may be passed, without meiting, may be dried in this oven. Raw sugаr may be approximately dried in 3 minutes and to constant weight in 10 mi es; 100 gram samples of cane bagasse are dried in less than 60 minutes; cotton saturated with water is dried in 10 minutes.

Refining rar sugars without boneblack: C. E. small and indications are that the departure from COATES. Raw sugars from the tropics have been neutral is a powerful factor in determining the refined off and on in Louisiana for a number of properties of the sugar. In addition, the sugars years. This was profitable on occasions when the were screened to determine average size of grain. margin between raws and granulated was high. A preliminary report was given on the importance During the past two years this margin has been so of improving and applying the so-called candy high as to offer exceptional profits to the refiner.

test to refined sugars. A number of Louisiana sugar houses purchased raw

A graphic method for estimating reducing sugars sugars during the last six months and refined them

in presence of sucrose : C. A. BROWNE. The slight by several different methods: Phosphoric acid and

reducing action of sucrose upon Fehling's copper lime; sulphur-dioxide and lime; filtercel alone; ac

solution introduces a considerable error in detertivated wood charcoals. At the beginning of the

mining reducing sugars in presence of large campaign, the yields were several per cent. below

amounts of sucrose. The author proposes a general those obtained in the standard bone black refinery

graphic method which consists of a chart containprocess, but as the season went on this difference

ing the reduction curves for dextrose in amounts was diminished until at the present time the yield

from 0 to 250 mgs. in presence of sucrose from 0 is about one per cent. short of good refinery prac

to 5gs. The correct amount of dextrose, corretise. The yields by the various methods are nearly

sponding to the amount found, is determined by the same. There is no reason why melting trop

finding the curve which passes through the interical raw sugars can not become a part of the rou

section of the coordinates for grams sucrose prestine practise in both cane apd beet sugar houses.

ent (as determined by Clerget) and mgs. dextrose The quality of the sugars obtained is excellent

found. The starting point of this curve on the and in the case of the activated charcoals the

base line indicates the correct amount of dextrose. sugars were beyond any criticism of any sort.

Commercial production of d-Mannite: W. B. Recent advances in defecation: W. D. HORNE.

NEWKIRK and C. F. SNYDER. At the request of The Dorr Clarifier has been devised to remove the the Army, the manufacture on a commercial scale insoluble impurities from cane juice. Hot limed of d-Mannite from manna was undertaken. The juice continuously enters the central well of the crude manna was dissolved in water in a melter superimposed settling compartment equipped with heated by steam coils. The liquor was 17° Brix. slowly revolving scraper mechanisms. Clear juice It was heated to boiling and defecated. Three flows from the periphery, and a thick mud is con- methods of defecation were employed. Method 1: stantly withdrawn from the bottom. The William- .005 per cent. phosphoric acid added to hot liquor son Clarifier aerates a warm defecated raw sugar and let stand for thirty minutes, neutralized with solution and then passes it through a long shallow

lime, allowed to settle and the clear liquid de

canted and filtered. The filtered liquor was boiled heating tank provided with suitable baffles, causing all insoluble matters to rise in a scum, which

in open pan to 30° Brix (hot), placed in tank and is mechanically skimmed off, while clear liquor is

crystallized. The crystals were separated in a

large centrifugal. Method II.: The raw liquor was continuously syphoned out below.

treated with 0.10 per cent. Kieselghur and filtered Comparative analysis of refined sugars: FRED- and the filtrate concentrated as above. Method ERICK BATES and associates at the Bureau of

111.: The raw liquor was treated with 0.5 per cent. Standards. A résumé was given of the results of

commercial vegetable carbon and filtered and the an elaborate and exhaustive study of about 250

filtrate concentrated as above. Method I. was the samples of refined sugars produced in the United

most satisfactory. The mother liquors from the States. One of the principal objects of this work

first crystallization were concentrated to 40° Brix was to determine the feasibility of preparing accu- and allowed to crystallize; the mother liquors from rate specifications and definitions of the refined the second crystallization were concentrated at sugars. The work included the determination of

60° Brix and a third crop of crystals obtained. the direct polarization, invert sugar, moisture and The mother liquor from the third crystallization ash. The acidity and alkalinity were determined was concentrated at 80° Brix and a fourth crop of by developing a new method, using the hydrogen crystals obtained. The final mother liquors were ion concentration with gratifying results. The concentrate to 80° Brix and a fifth crop of average acidity and alkalinity was found to be

crystals obtained. A tabulation is given of the

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melting points and rotations reported in the literature. The specific rotation was determined in water solution for the yellow-green mercury line and we find

(ME=:-0.255. Preservation of bagasse in sugar cane mill control: GUILFORD L. SPENCER. Formaldehyde has been generally used in preserving sub-samples of cane bagasse in preparing a composite sample, representative of several hours grinding. This has been ascertained to be only moderately efficient under modern milling conditions. The late M. Henri Pellet, in Egypt, suggested and used ammonia in protecting the samples. The author found this usually efficient but occasionally there is loss of sugar.

This suggested the addition of chloroform and preservation of the bagasse in an atmosphere of ammonia and chloroform. This mixture is apparently very efficient. Refinery press-cake holds its polarization during several weeks in the presence of this preservative. The solution for polarization must be acidulated with acetic acid before clarification with lead subacetate.

Glass vacuum pan for laboratory use: M. J. PROFFITT.

Changes in the polarizing constants of sugars during refining : A. F. BLAKE. The Clerget sucrose value for sugars, as pointed out by Browne at the Cleveland meeting, normally exceeds the polarization by about one third the percentage of invert. This is true of raw sugars as shown by numerous analyses, but in the products of a refinery, soft sugars and syrup, the value of the ratio (S-P)/I is very low. Analyses of sugars at all intermediary stages of refining are given, in order to determine where the change takes place. It is concluded that some change takes place during defecation and filtration of low test material and in the handling of the muds and scums due to action of lime on the invert sugar, but that by all means the principal cause of the reduction of the value of this ratio is bone-black filtration. The factor is strongly negative for the first material coming off the boneblack, but increases in following portions until in the last portion it is about equal or slightly exceeds material going on. The average value of the factor for all material going on is much higher than the average coming off. Since boneblack absorbs invert from first material and gives it up to later material it is supposed that by selective action it might absorb more

levulose than dextrose. This is proved by tests on invert sugar.

Another cause is the molecular rearrangement of dextrose and levulose into glutose, etc. A high value of the ratio in refined products indicates inversion during refining. Losses of sucrose figured upon Clerget values exceed those figured on polarization, while losses of organic material are much less.

A report on the sugar industry of France since the war: T. H. MURPHY. The French sugar industry, born of the Napoleonic wars, almost perished in the World War, being 66 per cent. destroyed. Formerly, the 213 sugar factories supplied all French consumption and 78,739 tons per year for export. Now the 60 small factories remaining can supply only a small portion of the nation's requirements, and about 400,000 tons per year are imported. One hundred and forty-two factories were 85 per cent. destroyed, and all copper coils, bronze tubing, copper and brass screens, in fact everything made of copper, bronze or brass, and all electrical equipment, was stripped out of the war-wrecked factories and taken to Germany. The plants where sugar machinery and equipment was made, suffered the same fate. The damage to sugar factories was over $89,000,000. Reconstruction in France has made strides, but on account of the highly specialized machinery and equipment required, the sugar industry, has, as yet, been able to accomplish very little. Photographs of destroyed sugar factories shown.

The composition and preparation of a sugar syrup of maximum solubility: R. F. JACKSON and C. L. GILLIS. One of the large branches of the sugar industry is the manufacture of syrups for direct consumption. If the syrup consists only of sucrose, the saturated solution may contain only 38.7 per cent. of the sugar. Such a solution is too thin for a desirable product and is susceptible to fermentation. If concentrated to a denser consistency, it becomes supersaturated and deposits sugar crystals. If, however, the sucrose is partially inverted, the density may be considerably increased, but if the inversion is carried too far, the relatively low solubility of dextrose limits the density to which the syrup may be concentrated. A study was made of the mutual solubilities of the three constituent sugars, namely, sucrose, dextrose and levulose in the presence of each other. The solubility of sucrose in varying proportions of invert sugar was determined to very high concentra. tions of the latter. Similarly the solubility of su


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