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On the Pacific coast, wheat farmers have generally found that bluestone-treated seed escapes wholly or in part from soil infection. Bluestone solutions (1 pound to 4 or 5 gallons of water) are so strong that heavy loss in seed germination occurs. To prevent this loss, the bluestoned seed is dipped in a lime solution. This double dipping adds considerably to the cost and labor concerned in the seed treating process. Inquiries are frequently received requesting to know if the lime can not be mixed with the bluestone and but one dipping given. As the lime counteracts the effects of bluestone on smut spores, this process is not advisable. In devising some means to meet the situation the writer devised tests using the lime sulphur-dip so universally used in spraying fruit trees for fungous pests. Preliminary tests with wheat and barley show the lime sulphur-dip at rather dilute solutions to be very effective against both stinking smut of wheat and covered smut of barley. As a thick coating of the dip adheres to the seed, it is quite effective against soil infection. The germ of seed wheat and barley dipped in a lime-sulphur solution even as strong as one part to one part of water gave, in these preliminary tests, no noticable deleterious effects on seed germination. If further more exhaustive tests confirm the preliminary ones, a fungicide which is much cheaper than bluestone and entirely lacking in destructiveness to the seed germ will have been secured.
UNIVERSITY OF California, BERKELEY, CAL.
W. W. MACKIE
A Text-book of Mycology and Plant Pathology. By JOHN W. HARSHBERGER. P. Blakiston's Son & Co., 1012 Walnut St., Philadelphia, 1917. With 271 illustrations, vii+779 pages.
Students as well as investigators in mycology and plant pathology will greatly welcome the appearance of the above named work, by Dr. Harshberger. This is perhaps the only American book of its kind which treats of mycology in its true relationship to plant pathol
ogy. The book is of special interest, as it is written by a man who combines the knowledge and the technique of the old and the young botanist. Dr. Harshberger's work is the result of twenty-seven years experience in teaching and in preparing men for the botanical profession.
Like all other of his works, Dr. Harshberger's present book is very exhaustive; indeed it may safely be called an encyclopedia of mycology and plant pathology. It contains a wealth of information all written in concise language. It is also abundantly illustrated, and the numerous references will be especially welcomed by students and investigators. A book of this nature should not be judged by some few imperfections, or errors, in spelling, but rather by its scope and its ability to cover the field in a precise way. In this the author seems to have succeeded.
The book is divided into four parts: Part I. deals with systematic mycology. It is divided into twenty-one chapters in which the Myxomycetes, the Schizomycetes and the Eumycetes are considered at length. The Myxomycetes receive a considerable share of attention and emphasis is laid on the pathogenic forms. A complete bibliography is also appended. The discussion of the Schizomycetes is taken up in a similar fashion as the Myxomycetes. The pages dealing with the fungi are preceded by chapters on histology, chemistry, physiology, ecology, etc. A comprehensive treatment of enzymes in fungi is also given. The chapter on the geographic distribution of fungi will be appreciated by the plant pathologist. The distinctive features of the taxonomic chapters on the fungi is that emphasis is laid on the forms pathogenic to plants.
Part II. takes up a general consideration of plant pathology. The various forms of disease, the predisposing factors, the symptoms, etc., are very clearly set forth.
Part III. deals at first with a list of specific diseases of economic plants. These are taken up alphabetically and the reader is referred to a list of fairly extensive agricultural experiment station bulletins. The second part of
Part III. goes into detailed account of specific diseases of plants in which the hosts are also taken up alphabetically. Only those diseases which are of economic importance are considered. The doubtful ones, or those of little economic importance, are omitted. Here plant pathologists will find ground to differ with the author in his choice of those specific diseases which he considers most important. The survey in the chapter of non-parasitic, or physiologic, diseases will be appreciated by the student.
Part IV. takes up a detailed account of laboratory and teaching methods. Here the author incorporates much of his own methods and technique. This part will be found of particular interest to the teacher of both undergraduate and graduate students. Part IV. is made up of forty-six lessons in which every phase of laboratory technique is elaborately and clearly set forth. Finally the book concludes with an appendix which considers the preparation of fungicides and insecticides, spray calendar, keys for determining species of Mucor, Aspergillus, Penicillium, Erysiphacea and the fleshy fungi.
The distinctiveness of the book is the extensive field which it covers in mycology and plant pathology. It stands by itself, in its difference from the average American text-book bearing on these subjects. The book fills a timely want, and it should find a place in every library of the teacher, investigator or student. J. J. TAUBENHAUS TEXAS AGRICULTURAL EXPERIMENT STATION
THE ROYAL COLLEGE OF PHYSICIANS1
THE four hundredth anniversary of the foundation of the Royal College of Physicians of London is an event which can not be allowed to pass without comment. On September 23, 1518, Henry VIII. granted the charter by which the college was constituted. He did so, moved by the example of similar institutions in Italy and elsewhere, and by the instigation of Thomas Linacre and others of his own physicians, and of Wolsey his chancellor,
1 From the British Medical Journal.
with a view to the improvement and more orderly exercise of the art of physic, and the repression of irregular, unlearned and incompetent practitioners of that faculty. The college consisted of eight persons known as elects," with power to elect from amongst themselves a President annually, and to choose the "most cunning and expert men" to fill vacancies as occurred in their number. At the same time it was enacted that no person except a graduate of Oxford or Cambridge, without dispensation, should be permitted to practise physics throughout England, unless he had previously been examined and approved by the president and three of the elects. The first meetings of the college were held at Linacre's private house in Knightrider Street, the front portions of which, comprising a parlor below and a chamber above, used as a council room and library, were given to the college during Linacre's lifetime. These small premisesthe ground on which they stood only measuring about twenty-four square feet-continued to be used for nearly a hundred years. But in 1581 they were enlarged, and a capacious theater added, in which to deliver the lectures founded by Dr. Caldwell and Lord Lumley, in 1583. Dr. Foster was the first Lumleian lecturer. A botanical garden, under the supervision of Gerard, was also secured. Linacre, founder of the college, learned both as physician and scholar, was president until he died in 1524. Of distinguished successors and benefactors of the college during its first hundred years of existence the names of Clement (1544), professor of Greek at Oxford; of Wotton, the zoologist; of Caius (1555), linguist, critic, physician, naturalist, second founder of Gonville and Caius College, Cambridge, antiquarian and designer of the insignia of office still used by presidents; of William Gilbert (1600), author of "De Magnete" and first physicist of the college, naturally occur to us. The last meeting in the old college in Knightrider Street was on June 25, 1614; the first meeting in the new college, in Amen Corner, Paternoster Row, was on August 23, 1614. Here, in April, 1616, Harvey
delivered the Lumleian lectures in which he is supposed to have expounded his doctrine of the circulation of the blood; two years later the first Pharmacopeia Londinensis was issued by the college. The civil wars reduced the college to the greatest distress. Unable to pay an assessment by Parliament of five pounds per week, and its rent to St. Paul's, it was in danger of being sold by auction, when Dr. Baldwin Hamley came to the rescue, purchased house and garden himself, and with the utmost generosity presented them to his colleagues two years afterwards. Prosperity followed, for in 1653-4 the munificence of Harvey enriched the college with a museum, a "noble building of Roman architecture," stocked with valuable and curious contents, and a library of medical books, treatises on geometry, geography, astronomy, music, optics, natural history and travels. But this prosperity was not long continued. After Harvey's death in 1657, the treasury was nearly empty, lectures were suspended, large numbers of physicians were living and practising without a license within the liberty of the college, examinations were discontinued. The creation in 1664 by Sir Edward Alston of upwards of seventy honorary Fellows, both brought unlicensed practitioners under the authority of the college and replenished its coffers. But in 1665, during the great plague, most of the Fellows and officers of the college fled the city, and thieves broke in and stole the whole of the contents of the treasury chest. On September 5, 1666, the great fire consumed the whole of the college buildings; only the charters, annals, insignia, some instruments and portraits, and 140 printed books in the library were saved. The premises in Amen Corner were never rebuilt, and the college remained homeless until its new buildings in Warwick Lane, designed by Sir Christopher Wren, were opened without ceremony on May 13, 1674. This commodious and stately building occupied four sides of a quadrangle enclosing a large paved court, on the east side of which was erected at Sir John Cutler's expense a spacious anatomical theater. The
other sides of the quadrangle contained the library, coenaculum, censors' room and other public apartments. At the back of the college were the botanical garden, and in 1684 a noble library building was presented by the Marquess of Dorchester. Here the college stood for 150 years; all that remains of it now is the beautiful Spanish oak wainscoting, the gift of Hamley, which lines the Censors' Room in Pall Mall, and two colossal statues of Cutler and Charles II, which may be seen in the Guildhall Museum. At the end of 150 years the college buildings had become dilapidated, Warwick Lane was a slum, the population and fashion had moved westwards, and a more convenient situation for the Royal College of Physicians was a necessity. Mainly through the influence of Sir Henry Halford, a grant of land was obtained from the Crown at a cost of £6,000 in Pall Mall East, and on it the present college building, designed by Sir Robert Smirke, was erected and opened with great ceremony on June 25, 1825. The premises in Warwick Lane were sold for £9,000. One may regret their disappearance, and that it is no longer possible to people them with the shades of those who have made the history of medicine and of this famous college during 150 years of its life. The names of such are Mayerne, Glisson and Sydenham, exponents of clinical medicine, followed by Radcliffe, Garth, Arbuthnot, Freind, Sloane and Meade, and last but not least, William Heberden. All of these have made their mark in the history of medicine, and directly or indirectly have been associated with the history of the college. The quartercentenary of the Royal College of Physicians of London reminds us that, in spite of modern progress, we can not afford to neglect the learning of past ages.
SUGGESTIONS REGARDING THE CAUSES OF BIOELECTRIC PHENOMENA
BIOELECTRIC phenomena constitute a group of facts for which adequate and satisfactory explanations have hitherto been lacking. It is my purpose in this paper to point out certain
significant correlations between these phenomena and the metabolic gradients which are now known to exist in organisms; and to propose an explanation of the former in terms of these gradients. The metabolic gradients were first demonstrated by Child in Planaria; subsequently he and his students extended the observations to include a large number of adult organisms, cells and embryos.1 This work has shown that the anterior, oral or apical end of organisms has the highest metabolic rate and that this rate decreases along the sagittal axis. A gradient in rate of metabolism therefore exists along this axis; and to a less extent along other axis of symmetry also. This fundamental discovery has furnished a basis for the interpretation of many hitherto entirely inexplicable biological facts,2 and I believe that it also throws light upon the nature of the bioelectric currents.
1 Child, "Individuality in Organisms," Univ. of Chicago Press, 1915.
2 Child, Jr. of Morph., XXVIII., p. 65; XXX., p. 1; Roux's Archiv, XXXVII., p. 136; Newman, Biol. Bull., XXXII., p. 314, are a few examples where such interpretation has been applied.
the most marvelous manifestations of pro-
The following suggestions are by no means
8 Alexander and Cserna, Biochem. Zeitsch., LIII., p. 106, have demonstrated that the oxygen consumption of the brain greatly exceeds that of any other part of the body.
The term metabolism is too well understood to require definition; it commonly signifies the sum of chemical processes which results in the production of new protoplasm or other organic compounds, or of energy. "Metabolic rate" simply means the rate at which these processes take place; and modern chemistry, particularly through the study of organic and other catalyzers, has taught us the supreme importance of rate in any chemical system. The metabolic rate is generally measured either by the rate at which the raw materials, particularly oxygen, for the reactions are used up; or by the rate of production of end-products, especially carbon dioxide. The extent to which a given mass of protoplasm is actually alive is determined by its metabolic rate; these chemical reactions, always building and destroying, are the very essence of the living; when they sink to a rate so low that only the most delicate means serve to detect them, the organism is practically lifeless, but when they burn intensely, physiology, I performed this experiment with the
4 Child, "Individuality in Organisms," p. 63; Tashiro, "A Chemical Sign of Life," Univ. of Chicago Press, 1917; Waller, "Signs of Life from their Electrical Aspect," London, 1903.
Am. Jr. of Physiol., VIII., p. 294. 6 SCIENCE, XXXIX., No. 993.
7 An additional statement regarding the meta-
common tubularian hydroid found there, called at
1. Permanent Differences in Potential.-In a number of cases we know both the metabolic gradient and the permanent differences of electrical potential along the antero-posterior axis. Thus Mathews in 1903 discovered that the head of hydroids is electro-negative to the stem, and that anterior levels are electronegative to posterior ones. Later, Child demonstrated that in these animals the head or any anterior level has a higher metabolic rate than any posterior level. Hydes found
that the animal pole of turtle and other vertebrate eggs is electronegative to the vegetal pole, and the anterior ends of vertebrate embryos electronegative to posterior regions. Child subsequently found in similar materials that the electronegative regions are also regions of high metabolic rate. Morgan and Dimon10 reported that the anterior and posterior ends of Lumbricus terrestris and Allolobophora (Helodrilus) fætida are electronegative to the middle. Mr. Bellamy has repeated this experiment and confirmed the result on Helodrilus caliginosus. In my work on the aquatic oligochates,11 I was able to show in a number of species that the anterior and posterior ends have a higher metabolic rate than the middle. The same state of affairs presumably exists in the terrestrial oligochates also, although these can not be tested by the available methods for demonstrating differences in metabolic rate.
In these cases the regions of high metabolic rate are always permanently electronegative
hydranths appear earlier on apical than on basal pieces. In animals so lowly organized as the hydroids, where the metabolic gradient is well marked only near the apical end, practically lacking near the base, and very plastic and readily alterable by external factors, it is easy to select conditions under which the basal pieces will regenerate hydranths as fast as or faster than the oral ones; such conditions are: using long pieces, taking pieces from the more basal regions of the stem instead of from the apical regions, using basal pieces near the place where a branch is about to form, slight depressing conditions, etc. (the mere fact that pieces do well in the laboratory is not evidence that no depression existed; in fact, depressed pieces are more likely to survive than vigorous ones). Since Garcia-Banus mentions none of these factors in his paper, not even stating whether his apical pieces are near the original hydranth or not, it is presumable that he failed to control or eliminate them, and that this explains why he was unable to obtain the same results as other investigators.
8 Am. Jr. of Physiol., XII., p. 241.
9 This work is largely unpublished. See, however, on amphibian embryos, Child, Roux's Archiv, XXXVII., p. 135.
10 Jr. Exp. Zool., I., p. 331. 11 Jr. Exp. Zool., XX., p. 99.
to regions of lower metabolic rate. This fact suggests the hypothesis that the metabolic differences are directly responsible for the differences in potential and that the latter are, therefore, of chemical origin. This is also the opinion of Child, and R. S. Lillie has recently come to a similar conclusion.12 I am also in accord with R. S. Lillie regarding the chemical process which is at the bottom of these differences in potential,-namely, that it is an oxidation and reduction phenomenon. In considering this matter, one must remember that when one states that a given region is electronegative, one means electronegative with respect to the galvanometer, exactly as one says that the zinc pole of a cell is the negative pole; actually the zinc pole is positive to the carbon or copper pole, and similarly the regions of high metabolic rate are in reality electropositive to regions of lower metabolic rate. If one considers now the familiar " action at a distance" experiment of chemistry, in which the oxidation is carried out in one beaker, and the reduction in another, one finds the electrical conditions thus produced to be identical with those observable in organisms. The current runs in the galvanometer from the reduction beaker to the oxidation beaker, and in the bridge of salt solution from the oxidation beaker to the reduction beaker. The region of oxidation is thus, as also in the region of high metabolic rate in the organism, electronegative galvanometrically, actually electropositive. We have abundant evidence that the metabolic gradient runs parallel to the rate of oxidation. In the organism, however, oxidation and reduction are not separated as in our experiment, but there in all probability, the electric difference of potential is due to difference in rate of oxidation at difference levels,-in other words, to a concentration cell with respect to oxidation.
2. The Current of Injury.—It has long been known that any cut or injured surface is electronegative (galvanometrically as explained above) to intact surfaces. In this laboratory we have frequently observed that such injured surfaces always have a higher metabolic rate 12 Biol. Bull., XXXIII., p. 181 ff.