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which on the coin is circumscribed by the muliebri " to attend the lectures of Socrates name METAPENN, i.e., of the Megarians, and of his returning to Megara the next day has been published in the United States as in the same disguise. In this book Head representing Euclid the mathematician. This gives the date of the coin as “ Cir. 146 B.C. unintentional historical misrepresentation ap- or later"; in his Historia, quoted above, he pears in the publication, “ A Portfolio of Por- gives, “Imperial Times?". While Head thus traits of Eminent Mathematicians” (1896), expresses uncertainty as to the exact age of issued by the Open Court Publishing Com- the coin, he entertains no doubt as to the pany, in Chicago, a firm which in general has head-dress representing woman's apparel that done as much as any other in America to was worn by Euclid of Megara when on his advance a sound knowledge of the history of way to and from the lectures of Socrates. mathematics. The picture of Euclid of It is therefore established with as great Megara is given as that of the mathematician, certainty that this coin does not give the bust Euclid. In the memorandum accompanying of the mathematician Euclid as it is estabthe picture occurs the statement, “ the name lished that this mathematician was not Euclid Megara is frequently coupled with his [name] of Megara. on the early portraits as in this case.”

FLORIAN CAJORI The statement just quoted, in so far as it UNIVERSITY OF CALIFORNIA relates to the coin portrait in question, is in conflict with numismatic authority. A speci

RAINBOW BY MOONLIGHT men of the coin referred to is in the British

TO THE EDITOR OF SCIENCE: In connection Museum and has been described by the great

with the case of the rainbow at night reauthority on coins, Barclay V. Head, who

ported by Frank L. Griffin in SCIENCE of speaks of this coin as follows:2

March 11, the following case may be of METAPENN. Bearded head of the philosopher interest: At Burge, Nebraska, a rural post Eucleides of Megara, veiled and wearing ear-ring office about eighteen miles southwest of

This remarkable type refers to the story that Valentine, on September 4, 1917, at about Eucleides attended the lectures of Socrates in the

9 P.M. a rainbow appeared. The moon had disguise of a woman, the Athenians having passed

risen about an hour previously and a thuna decree that no citizens of Megara should be admitted within their walls. (Aulus Gellius, Noct.

derstorm was coming up in the west, the rest Att., VI., 10.)

of the sky being clear. A rainbow began to

form and it continued to become brighter In his catalogue of Greek coins Heads

until a complete arch was formed. It was quotes the Latin passage from Aulus Gellius,

very distinct, but was nearly white and the Roman writer of the second century A.D.,

showed the prismatic colors very faintly if referred to above, who had studied at Athens.

at all. The passage tells the story of Euclid's going

C. J. ELMORE to Athens disguised in a “tunica longa Corolla Numismatica ... in Honour of Barclay

QUOTATIONS V. Head,” Oxford University Press, 1906, pp. 368– 386.

BRITISH DYESTUFFS CORPORATION 2“Historia Numorum, a Manual of Greek The situation in which the directorate of Numismatics,” by Barclay V. Head, Oxford, 1911,

the British Dyestuffs Corporation finds itself

is a remarkable one. At the registration of 3«Catalogue of Greek Coins, Attica—MegarisAegina,” by Barclay V. Head, D.C.L., Ph.D.

this company in May, 1919, as a result of Edited by Reginald Stuart Poole, LL.D., London,

amalgamating British Dyes, Ltd., of Hudders1888, p. 121. See a drawing of the coin in Attica,

field, with Messrs. Levinstein, Ltd., of Blacketc., Plate XXI., 14,

ley, the appointment of Sir Joseph Turner as

p. 394.

commercial managing director, and of Dr. juncture; on the other hand, the board can Herbert Levinstein as technical managing di- scarcely escape the reproach of having allowed rector, was designed to maintain the interests an impossible situation to continue far beyond of both groups, and to benefit the united enter- the point at which a surgical operation had prise by the special contribution of knowledge become an obvious necessity. Having regard and experience which each of these gentlemen to the immense scientific and national interwas expected to make. At the meeting of ests which are involved in the ultimate sucshareholders in Manchester on Friday last it cess of this enterprise, and to the large sum was announced that Sir Joseph Turner and of public money which has been invested in Dr. Levinstein, while retaining their seats on the corporation, its future conduct demands the board, have been superseded as managing very careful scrutiny.-Nature. directors by Sir Henry Birchenough, the chairman of the corporation, Sir William Alexander, and Mr. Vernon Clay.

SCIENTIFIC BOOKS It is no reflection on the new managing Practical Plant Biochemistry. By MURIEL directors to express the opinion that the posi- WHELDALE Onslow. Cambridge University tion thus disclosed must arouse grave mis- Press, 1920. Royal 8vo, pp. viii + 178. giving amongst all those who recognize the

Price 15s. net. foundation of a self-supporting synthetic dye- It is being recognized by students of the making industry as a matter of the greatest plant sciences that a thorough understanding national importance. Disregarding the woe- of plant chemistry is essential to the solution ful absence of harmony which appears to be of their problems. This knowledge has been indicated, the aspect of this rearrangement usually obtained, on the one hand, from orwhich causes anxiety to chemists is the fact ganic chemistry, and on the other, from plant that, at a time when all the scientific knowl- physiology. It is the gap between these two edge and commercial energy available in this

sciences that this book is designed to fill. The country should be correlated in a concerted

author has made a real contribution to the effort to establish an industry which, more

study of plant chemistry. As in her former than any other, depends for success upon the

book on

“ The Anthocyanin Pigments of combination of these factors, two of the most Plants," she has presented a very clear and experienced practitioners should be removed

comprehensive discussion; however, in the few from very intimate association therewith.

pages of the present volume it is impossible The proper and perfectly natural request

to give more than a cursory discussion of the for an investigation put forward by the share topic. The book is essentially a laboratory holders met with a cold response from the

manual, which contains well-chosen experiboard, and the declaration by the chairmen ments that have been tested in practical that a general meeting is not the occasion

classes. Through these experiments the stufor an explanation of such peculiar circum- dent learns to extract from the plant itself stances is one with which many will sympa- the chemical compounds of which it is comthize; but the public is entitled to full infor

posed and to understand something of their mation at the earliest convenient opportunity.

chemical properties. As an introduction to Pending more precise knowledge of the facts,

each chapter, there is presented the fundait would not be fair to the late managing mental principles and relationships of the pardirectors, or to the board, to pass judgment ticular class of compounds studied in the exon their action. If, however, as the published periments. statements at present suggest, incompatibility The volume is divided into the following of temperament is the cause, chemists will chapters: I. Introduction. The synthesis of regard them as having failed in realizing the various classes of compounds, and the their responsibility to science at a critical chemical reactions by which they are brought

about, are discussed. II. The Colloidal State. It is appropriate that the book should begin with this topic, since it is essential for an understanding of the chemistry of cell protoplasm; but this is the least comprehensive and complete of any of the chapters. The two fundamental types of colloidal solutions, suspensoids and emulsoids, are treated and their characteristic properties illustrated. III. Enzyme Action. The underlying principles of enzyme action are briefly discussed and the behavior of different enzymes illustrated by those contained in yeast. The discussion of other enzymes follows in connection with those chapters dealing with the respective substrates. IV. Carbon Assimilation. It is emphasized that chlorophyll is perhaps the most important factor in plant metabolism. V. Carbohydrates and their Hydrolyzing Enzymes. Of all the subjects in plant chemistry which deserve careful treatment it is that of carbohydrates, and to it the author has devoted more space than to any other. There is a careful consideration of the properties and characteristics of the various carbohydrates, their synthesis and relationships in the plant. The monosaccharides, disaccharides and trisaccharides are most thoroughly treated, the latter under the following topics: pentosans, starches, dextrins, inulin, mannans, galactans, gums, mucilages, pectic substances and celluloses. VI. The Fats and Lipases. VII. Aromatic Compounds and Oxidizing Enzymes. The more widely distributed aromatic plant products are grouped: the phenols and their derivatives; the aromatic alcohols and acids including the tannins; the flavone, flavonol and xanthone pigments; and the anthocyanin pigments. The greater portion of the chapter is devoted to the plant pigments and oxidizing enzymes. VIII. Proteins and Proteases. The properties and chemical reactions by means of which the proteins can be detected are studied, and experiments follow which illustrate the method of extraction of the proteins from characteristic grains and seeds. IX. Glucosides and Glucosidesplitting Enzymes. Besides the glucosides of the pigments previously discussed the cyano

phoric glucosides receive chief attention. X. The Plant Bases.

In the preface the author states that the book presents an aspect of plant biochemistry which up to the present time has received very little consideration in teaching. This is not entirely true in America, for at the University of Minnesota there have been offered for several years courses in phytochemistry and biochemical laboratory methods with particular reference to plant products. It is rather a coincidence that the subject matter of our courses should be similar, beginning with the colloidal state of matter and following with the classes of compounds found in plants. These courses through lectures and laboratory have presented to the student the same viewpoint for which this book was designed. Mrs. Onslow is to be commended for her pioneer work in the publication of a text on this important subject. From the mechanical stand. point the book is up to the usual standard of the publications of the Cambridge University Press. It is to be regretted, however, that in all probability the price will prevent it being used in many cases where it could profitably be employed.

CLARENCE AUSTIN MORROW DIVISION OF AGRICULTURAL BIOCHEMISTRY,

UNIVERSITY OF MIN ESOTA

Anthropometry. By. Aleš HRDLIČKA. Wistar

Institute of Anatomy and Biology, Philadelphia. Pp. 163.

Anthropologists and all other workers who have occasion to make use of anthropometry have long been handicapped by the lack of any adequate and up-to-date manual of anthropometry. Now, at length, they have at their disposal a compact and comprehensive treatise on the subject written by one of the most experienced and competent investigators in the field, Dr. Aleš Hrdlička, curator of the Division of Physical Anthropology, U. S. National Museum. As a laboratory manual in physical anthropology and as a handbook for the use of field investigators of physical characters in man, this book should prove invaluable.

The work very properly begins with an an- long also to this category of features which notated translation of the Monaco and Geneva must be described rather than measured. Agreements for the Unification of Anthro- Perhaps it may be said that the greatest pometric Measurements. There follows a con- value of this work on anthropometry lies in cise treatment of the preliminaries of the the fact that it represents the perfected subject, such as preparation, instruments, methods of one of the most skilled and best landmarks, recording grouping of subjects, qualified practitioners of the science. Experts estimation of age, admixture of blood, patho- may differ as to the value of this or that logical conditions, etc. The various topics are measurement, or may prefer their own techhandled with clarity and include much orig- nique in individual cases, but this book is in inal data in regard to general methods. There general reliable and conclusive. A careful is a sane appraisal of the various anthropo- follower of its methods can not fail to secure metric instruments and accessories employed completely adequate physical data in any in investigations.

general anthropometric investigation. The section on the anthropometry of the

E. A. HOOTON living deals with a selected list of the most

HARVARD UNIVERSITY important measurements and observations as determined by the experience of the author.

SPECIAL ARTICLES The directions given are very clear and in- SUBEPITHELIAL GLYCOGEN CELLS IN EMBRYO clude many practical suggestions tending to

AND RECENTLY HATCHED FISH promote facility of observation and accuracy In April, 1912, while studying the developof result.

ment of the yellow perch (Perca flavescens) I The anthropometry of the skeleton is satis- discovered numerous cells filled with glycogen factorily treated and includes a description of located just below the flat epithelium coverthe invaluable system of visual observations ing the surface of the embryo. The embryos elaborated by the author. In the opinion of in which I demonstrated these cells had been the reviewer this standardization of morpho- developing in the laboratory for twelve days. logical observations constitutes a contribution Upon the addition of a few drops of tincture to anthropometric method of first importance, of iodine to the water in the saucer in which and the section dealing with it might advan

the embryos were contained it was noticed, tageously be expanded. It is to be hoped that upon microscopical examination, that there Dr. Hrdlička may find time to publish else

were many round or oval cells, stained a redwhere a series of articles illustrating the nor

dish brown, scattered over the surface of the mal or medium development of the various

embryo, and especially marked in the fins. I morphological characters and the extremes of

have repeatedly studied these cells in the their variations. Such illustrations, together yellow perch and some other species of fish with a discussion of the extent and signifi

since I first observed them, and I have found cance of variations, would provide a standard

them so interesting that I wish to make a

record of some of my findings. basis for judging the degree of development

The embryos of the yellow perch are espeof immensurable characters. At the present

cially well adapted for microscopic examinatime the value of such observations is depend

tion, as they are exceedingly transparent, and ent upon the accuracy and experience of the

retain their transparency to an advanced stage individual investigator. It is becoming ap

of development. The development of the eggs parent to physical anthropologists that mor

takes place rapidly at the ordinary temperaphological differences of detail that do not

ture of the laboratory. At the end of the lend themselves to measurement are of pri

fourth or the beginning of the fifth day after mary importance in distinguishing races.

the first division of the egg the embryo begins Many important functional adaptations be

to make spontaneous movements of its body, and the rudimentary heart commences to beat. nucleus. A very weak solution of iodine No glycogen cells can be detected at this time, formed by adding a drop or two of the tincbut about the beginning of the sixth day they ture to 5 c.c. of water gives the cells their appear as minute dark brown spots after the characteristic color in a few seconds if the application of the dilute iodine solution. The animal has been removed from the egg englycogen cells increase in size and become velopes. If the embryos retain their gelamore granular during the further development tinous envelope they are stained in a few of the fish. At the time of the appearance of minutes, and it is easy to follow the gradual the cells the embryos are covered with a single staining of the cells before the animals are layer of very thin flat epithelium. The inter- killed by the iodine. cellular substance of the epithelial cells can be At the time of the first appearance of the easily and strikingly stained, after the appli- glycogen cells there are no blood globules in cation of a weak iodine solution and wash- circulation, but these are first seen a day or ing in water, by immersing the animal in a two later. At a little later period the liver dilute aqueous solution of methylene blue for is formed, and may be stained a brick red by a short time. The blue staining fluid forms a the iodine solution. The liver cells do not dark precipitate with the iodine in the cement contain glycogen granules but are diffusely substance, and forms zigzag lines which de- stained a lighter and more reddish color than limit the cells in the clearest manner. The the subepithelial glycogen cells. dark lines may be seen to cross the glycogen After a certain degree of development of cells in many places, indicating that these the fish the number of the glycogen cells becells are beneath the epithelial covering. comes gradually lessened by absorption. As I

The glycogen cells are usually more or less have had the perch under observation for only elliptical and their dimensions vary with their a limited time after hatching I have never stage of development. When they first appear witnessed the complete disappearance of the their diameters may vary within the limits of cells. In and after the third week of devel34 and 104. At this time the protoplasm of opment their number becomes much smaller. the cells forms a ring surrounding a large At that time the glycogen cells of the tail may central vacuole containing the glycogen gran- be crowded into its edge, and those of the ules. One part of the ring is usually thick- pectoral fins arranged in columns radiating ened, and contains an elongated elliptical or in the direction of the striation. This change crescentic nucleus. As the cells enlarge with in position is probably due to the growth of the advanced development of the fish their other tissue elements which displace the glyvacuoles encroach on the protoplasm until the cogen cells. In advanced development I have cells are converted into microscopic sacs of noticed in the tail fin many smaller mesoglycogen, in the walls of which a long ellip- blastic cells which are not stained with iodine. tical or reniform nucleus can usually be I have found many glycogen cells, very found. At this stage the diameters of the similar to those of the yellow perch, in recells may be 154 to 25d, and the granules, cently hatched pike-perch or wall-eyed pike, stained a mahogany color with iodine, are and in the small-mouthed black bass, but some chiefly found just below the cell membrane. differences in the appearance of the cells in A number of these granules may coalesce and the different species, and in the solubility of form a rod-shaped body in the interior of the their glycogen granules were noted. The cell. Sometimes three of the rods unite in glycogen cells of the pike-perch are coarsely the shape of a Y. The stained granules of granular, and their glycogen dissolves very glycogen dissolve with considerable rapidity rapidly in the dilute iodine solution. The in the water containing the preparation, and nuclei of the cells are not so apparent as many of them disappear after a few minutes, those of the yellow perch. The glycogen cells leaving the thin cell membrane containing the of the pike-perch may be seen under the

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