THE BUTANICAL -GAZEI FE ————e EDITORS: JOHN MERLE COULTER anp CHARLES REID BARNES te se VOLUME XLV ae JANUARY- JUNE, 1908 TABLE OF CONTENTS Sporogenesis in Nephrodium. Contributions from the Hull Botanical — 106 _ — LIV) - Shigéo Yamanouchi 1 The development of the pollen of Sameoe — pla - M. Louise Nichols 31 hasnt of ice py “a vith event our figures - James Ellis Gow 38 The toxic effect of certain common sie of the soil on plants (with one figure) -) - - Florence N.Magowan 45 The toxic action of certain organic ont constituents (with seven figures) - - Oswald Schreiner and Howard S.Reed 73 Some new cases of Mendelian inheritance —_ four figures) - George Harrison Shull 103 The pista action me — and a (with three figures) - - - W.J.V. Osterhout 11 figures) 7 Nereocystis and Pelagophycus - William Albert Setchell 125 eee NE ee eee ee on ical Laboratory 107 (with plates VI-VIII)- - Shigéo Yamanouchi 145 tions from the Hull Botanical Laboratory 108 Heinrich Hasselbring 176 The relation of ~~ societies to — —_ - Edgar = Transeau 217 nine figures) Fores stuis of ston tension and toxin | 3 . 4 v The imilation of Penicillium, Contriba- | | vee i omc Pond aes vi CONTENTS [VOLUME XLV BRIEFER ARTICLES— The physiological constants of plants commonly used in American botanical laboratories - Sophia Eckerson 50 The condition of certain winter buds - William in. and Mary E. Behney 54 Notes on cleistogamy of grasses (with five Viesue Agnes Chase 135 A new species of Achlya (with six figures) - W.C. Coker and J. D. Pemberton 194 On the origin of angiosperms - -~— - Hans Hallier 1096 The generic name of Goldmania_ - - - J. M. Greenman 108 Lucien Marcus Underwood (with portrait) - Editors A convenient traveling balance (with two fant: W. W. Stockberger 269 The toxic action of certain — constituents.— A correction - ee a Editors 271 Variations i in | Helianthus - ce we A, Cocker. 228 Ted ith four fi ) R. Wilson Smith 338 An abnormal Porella polyp vith ise F. M. Andrews 340 On the contents of ‘he lic: enka of a specimen of Lagenostoma ovoides — two ae) ee er Margaret Benson 409 The embryo of Ceratozamia. x descloicnt study. Contributions from the Hull Botanical Laboratory 111 (with seven figures) - - Helen A. Dorety 412 LIrERATURE - - - - ~- 55, 137, 199, 272, 341, 417 under - Papers | mtced a “Notes fo a Students” are in- ~— ae eas, 210, 287, 360, 483 DATES OF PUBLICATION [ioe 16; 3 eer 3s: No. 3, March 12; No. 4, April 14; No. a ee es P. 232, footnote 7, for 379 read 397. P. 237, Table V, ete XVII, column, fourth number, ee Sete ge eo eee te nig oa oe ia ee AS THE BoTANICAL GAZETTE January 1908 Editors: JOHN M. COULTER and CHARLES R. BARNES CONTENTS j Sporogenesis in Nephrodium — Shigéo Yamanouchi The Development of the Pollen of Sarracenia ™- Louise Nichols Embryogeny of Arisaema triphyllum ‘James Ellis Gow | The Toxic Effect of Certain Common Salts of : , the Soil on Plants ee Florence N. Magowan | : | Briefer Artic’ s The Phy: nogical Constants of Plants Commonly Used in : . Ame .can Botanical Laboratories Sophia Retersen. es 7 ‘The Condition of Certain Winter Buds William Moore aenere gee Pe : ee Current Literature ao a 2 2 News. oe "The University of Chicago Press | CHICAGO and NEW YORE Wiliam ‘Wesley aad Son, Londen” Che Botanical Gazette A Montbly Journal Embracing all Departments of Botanical Sctence q Edited by JOHN M. CouLTER.and CHARLES R. BARNES, with the Sa of other members of the 4q botanical staff of the University of Chic _ Vol. XLV, No. 3 Issued January 16, 1908 CONTENTS ’ ee 2S IN NEPHRODIUM. CONTRIBUTIONS FROM THE HULL BOTANICAL LAB- 4 Y 106 (WITH PLATES I-Iv). Shigéo Yamanouchi - I ; THE oo OF THE POLLEN OF SARRACENIA golente PLATE Pie M. Louise : Nich _EMBRYOGENY OF ARISAEMA TRIPHYLLUM adaaally TWENTY-FOUR arena, nue Ellis | THE TOXIC EFFECT OF CERTAIN COMMON SALTS OF THE SOIL ON PLANTS 4 ( H ONE FIGURE). Florence N. Magi ee | BRIEFER ARTICLES ; THE PHYSIOLOGICAL CONSTANTS OF PLANTS COMMONLY USED IN AMERICAN BOTANICAL Eck LABORATORIES. Sophia Eckerson - + - 50 q THE CONDITION OF CERTAIN WINTER Buns. William Moore and Mary E. Behney - 54 _ CURRENT LITERATURE 4 BOOK REVIEWS - - eee ee ee DANISH STRAND VEGETATION. A NEW TEXTBOOK OF BIOLOGY. WETTSTEIN’S HANDBUCH. MINOR NOTICES - - - - ee ee Se te oe NOTES FOR STUDENTS : vee - - : : . - ze - ey eh 72 Botanical Gazette is published ewes “The subscription ee is $5.00 per year: the price _ of single copies is 50 cents. [Postage is prepaid by the publishers on all orders from the United States, Mexico, nras Porto Rico, Pa anama Canal Zone, Republic of Panama, Hawaiian Islands, Phi ne Islands, Guam, la (Samoa), Shanghai . “Postage is charged extra as follows: og Conta = cents” ‘on annual ciineahia s (total $5. 35), 0 on single gree 3 cents (total 53 cents); for all other cou inthe Postal Union, 84 cents on annual subscriptions (total $5.84), on single gpl . cents (otal or ; -‘S Remittances should be made payable to The ise of Chicago Press, and should be in Chicago or k exchange, postal or express money order. local check sagearcleng ro cents must be added n. . William Wesley & Sos, 28 Bact Street, Strand, London, are are appointed sole European agents ts and are authorized to quote the following oe Yearly subscriptions, including postage, * 45. each; single — & postage, 2h Ocak eo Claims for missing numbers should be made within the secstin Sciiwiing. (hae dk andes eateks of publi cation. The publishers — - eenigd missing numbers free only when they have been lost in transit. Busine: be addressed to The University of Chicago Frese; Eiengo, A for +h 234, 3 Aja tn 6h Chicago, hin TTT I i daik seoecsted to write scientific and proper names with particular care, , to use tiie metric ne zh eo ‘citations to follow the form shown in the pages of the BorawrcaL Papers in excess of thirty-two printed pages are not accepted unless the author is willing to pay ie cost ofthe additional pages, i ase the nmr af pgs nthe volume creping Mmereased. Rit: t tio . . we - . Light Waves and Their Uses By Albert A. Michelson 1. Wave Motion and Interference. 5. Light Waves as Standards of Length. f the Efficiency ofthe Micro- 6. Analysis of the Action of Magnetism on zi peer ariagmsd saa and atcteomneter Light Waves by the Interferometer and 3 ——- of Interference Methods to the Echelon of Measurements of Distancesand Angles. 7. Application of Interference Methods to 4 Application of Interference Methods to Astronomy. Spectroscopy. 8. The Ether. With 108 text figures and three full-page lithographs. Numerous practical applications of recent theories in optics together with ed illustrations and a ns of apparatus add materially to the value of this boo Students of physics and astr ronomy will find here an admirable ciktanigions n of the some- what scattered rete of the subject, presented in an original and entertaining manner. Price $2.00 net; $2.13 postpaid, University of Chicago Press Chicago and New York The An Indispensable Book for Students of Botany Methods in Plant Histolo gy SECOND EDITION—ILLUS TRATED By Cuarwes J. Cua AMBERLAIN, Py.D. Instructor in Botany in the University of Chicago le BOOK contains directions ve momen. and preparing ae material for microscopic inves tigation. ased upon a course in botanical micro- technique, and is the first apiece manual t ublished on aes subject. raffin method, the celloidian method, and the gly cerine {n later chapters specific directions are given for reparations as are needed by thos . formulas are given for the reagents reparing the second edition the ance in oe science since the book first appeared. S methods for securing the various reproductive phases in the Algae and Fungi have been outlined in a ractica way, — in discs such ion a “wap, 9, ct, net, $2.25; postpaid, $2.39. r 4E UNIVERSITY OF CHICAGO PRESS Bulletin of Recent Publications and Winter Announcements of Che Ciiversity of Chicago Press English Poems Selected and Edited, with Illustrative and Explanatory Notes and Bibliographies, by WALTER C. BRONSON, Professor of English Literature, Brown University Vol. IV, The Nineteenth Century, 635 pages, 12mo, cloth; net $r.00, postpaid $1.15. Library Edition, net $1.50, postpaid $1.6 In preparing this series, Professor Bronson is providing for college students and others a more a and generally available selection of Englis made befo When completed it will comprise four volumes. English te in oo Middle-English poems, early drama, and old ballads; Volume II will cover the Eliz and Caroline periods; Volume III will be devoted to the Restora- tion and the dohieorie a. while Volume IV (now ready) covers the nineteenth century. Special The volumes are being The ai sees of “The Nineteenth Century” i Aut oems have been chosen ger for their merit and for their sete tice in the ory of - ngs Risratuee! e book is therefore pe an anthology, or we gaan of the best poems. It is eee of - ems that illustrate the different periods and phases of set work of indiv ses poets, and the rise, growth, decline o slp ry. nw eres er that and >.. which the ure; (2) state- issued at intervals of about six mon a is thus esa in the Lapin: Bg on the ing of a poe r give circumstances spithesea Nig Ww grr Pe composition of it, or illustrate the poet’s method of work; (3) the poet’s theory of pe and his bsg ilos copy of ite, when these can be gi ven in his (4) variant readi ok ms, s cle ae othe Palace ‘of mi 2 tie oes ng 0 special interest and significance; (5) quo sources and parallel passages, or — to to show the poet’s literary relations raw materi al; si ici — on “aee oO see from them erary mov select bliography, adapted to the ieats ‘of shana oil follows the y the author or his friends which ‘throw light cats of American Literature By ANNIE RUSSELL MARBLE 94 pages, 11 plates, small 8vo, cloth; net $1.50, postpaid $1.64 Recounts in detailed study and largely from original sources the lives and services of a group of typical writers of the Revolutionary and National periods. ere are bio- graphical and critical studies of Francis Hopkinson, Philip Freneau, John Trumbull and his ““Hartford wits,” Lissa Dennie, William Dunlap, and early playwrights, temporaries in fiction. The book is illustrated by several half-tones of rare portraits, broadsides, and title-pages. Literature in the Elementary School By PORTER LANDER MacCLINTOCK 320 pages, 12mo, cloth; net $1.00, postpaid $1.12 The book gives a series of detailed studies on the choice and teaching of the various kinds of stories; on poetry; ma; on myth as literature; on the correlation of return to finally a list of titles in literature for each of the elementary grades, offered as a Suggestion to the inventive teacher, but also defended as a working programme tested by experience. rer 2 UNIVERSITY OF CBC AGO PRESS Adam Smith and Modern Sociology: A Study in the Methodology of the Social Sciences By ALBION W. SMALL, Professor and Head of the Department of Sociology 7 in the University of Chicago 260 pages, r2mo, cloth; net $1.25, postpaid $1.36 The volume is the first of a series which the author will edit on the preparations for sociology in the fragmentary work of the nineteenth-century social sciences. The main argument of the book is that modern sociology is virtually an attempt to take up the larger programme of social analysis and interpretation which was implicit in Adam Smith’s moral philosophy, but which was suppressed for a century by prevailing interest in the technique of the production of wealth. It is both a plea for revision of the methods of the social sciences and a symptom of the reconstruction that is already in progress. Women’s Work and Wages: A Phase of Life in an Industrial City By EDWARD CADBURY, M. CECILE MATHESON, and GEORGE SHANN 383 pages, 8vo, cloth; net $1.50, postpaid $1.61 . The authors give, for the purposes of the student and social worker, a systematic | and comprehensive statement of the facts and theories of women’s work and wages and the complex attendant problems. The valuable work done in late years by various writers and associations is brought into line with the facts gathered by original investigation of a most exhaustive nature. : Outdoor Labor for Convicts By CHARLES RICHMOND HENDERSON, Professor and Head of the De- partment of Ecclesiastical Sociology in the University of Chicago 170 pages, 8vo, paper; net 75 cents, postpaid 83 cents ‘ This little volume gives English translations of all the reports made to the last Inter- — national Prison Congress at Budapest, together with accounts of various farm colonies in Belgium and Switzerland, and of outdoor work of prisoners in the United States. The book contains the largest body of expert opinion and of fact to be found anywhere on this subject, and the conclusions offered are based on the results of experiments made in nearly all civilized countries. Chapters in Rural Progress i By ercrdiiak L. BUTTERFIELD, President of the Massachusetts Agricultural ollege 276 pages, 8vo, cloth; net $1.25, postage extra The increasing interest in rural matters, springing from the renewed devotion to out- door life, and now including the technical aspects of modern agriculture, is gradually being © broadened to embrace the field of economic and social investigations. At present the literature regarding the sociological phases of rural life is parhcularly Snack President Butterfield’s book emphasizes the social aspects of rural f the newer move- ments resulting in the expansion of country life. LHE UNGPVERSITY OFf CHICAGO PFRea. The True Nature of Value By RUFUS FARRINGTON SPRAGUE 190 pages, 12mo0, cloth; net $1.00, postpaid $1.10 Mr. Sprague is not a professional economist, but a successful manufacturer, whose attention has been for many years directed to the abstract principles underlying exchange. In the public discussions of a few years ago on the subject of a monetary standard he took an important part, and he was the candidate of the ‘Gold Democrats” for governor of Michi- gan. He has developed a theory of exchange value which resembles in some points that of Bastiat, but is much more elaborately developed and in many respects entirely new. The book deserves the attention of all economists. Sex and Society: Studies in the Social Psychology of Sex By Livegrees I. THOMAS, Associate Professor of Psychology in the Univer- sity of Chicago 334 pages, 12mo, cloth; net $1.50, postpaid $1.65 Few books of this nature have attracted so much attention. It is a popular account of the results of studies in a field to which the general reader has scant access. Thoroughly scientific in method, and embodying the latest conclusions of experts, it deals with a subject of universal interest and is written in a style that holds the attention from beginning to end. dagen) Thomas moves with an expert discern- The book has genuine interest for the general ment, man} ing in prevalent Treader and makes a direct appeal to the student of ace eer builds up a consistent objective picture sociology.—Literary Digest. of woman’s sociological status—The Dial. A strong, a well-balanc — and well- arranged book.—A. L. A. Booklist. The Development of Western Civilization: A Study in Ethical, Economic, and Political Evolution By J. DORSEY FORREST, Professor of Sociology and Economics in Butler College 420 pages, 8vo, cloth; net $2.00, postpaid $2.17 A scholarly discussion of the various elements from which the civilization of Europe was formed, the part played by each in the shaping of modern society, and the social phenomena which result from this course of development. Professor Forrest has gathered facts of a and afar more mapeicty and beautiful ere Pate philosophy from _ sources, both ancient and — society—than could have been obtained fro modern. He has succeeded in weaving ieee into recital of Scuigusibes history.— Boston T: vacoeuia A Short History of Wales By OWEN EDWARDS, Author of The Story of Wades, etc. 162 pages, 12mo, cloth; net 75 cents, postpaid 83 cents This book, by one of the most distinguished of living Welsh scholars, will supply a long felt want. It aims at giving the general reader a simple and intelligible outline of the history of Wales, and is particularly fitted to be used as supplementary reading in schools. It covers the entire history from prehistoric times to the present day. The volume is fully equipped with summaries, pedigrees, and maps. THE UNIVERSITY OF: CHICAGO PRES@ The Tragedies of Seneca . Translated by FRANK JUSTUS MILLER, Associate Professor of Latin in the} University of Chicago 445 pages, 8vo, cloth; net $3.00, postpaid $3.20 This is a new translation of the ten tragedies which have come down under the name of | Seneca. They are rendered in English blank verse, with appropriate lyric meters for the | choruses. The work is enriched and its value greatly enhanced for both classical and English students, as well as for the general reader, by an introduction on the influence of Seneca upon early English drama, contributed to the volume by Professor John M. Manly; also by a review of the Roman historical drama in connection with the Octavia, by comparative | analyses of Seneca’s tragedies, and by a comprehensive mythological index and glossary. Dramatic Traditions of the Dark Ages By JOSEPH S. TUNISON 35° pages, 12mo, cloth; net $1.25, postpaid $1.36 The critics of the ancient drama never get beyond Seneca—if indeed they go so far—and | students of the modern stage usually begin with the thirteenth century. This book aims to cover the interval. __ Mr. Tunison has the skill and liveliness of method The quantity of his results can not easily be ; which enable him to marshal this wonderful array of | measured.—Springfield Republican. acts—New York Times. The Interpretation of Italy During the Last Two Centuries: A Contribution to the Study of Goethe’s ITALIENISCHE REISE , By CAMILLO VON KLENZE, Professor of German Literature in Brown : * University 150 pages, 8vo, cloth; net $1.50, postpaid $1.62 | With a view primarily to throwing light on Goethe’s estimate of Italy, the author traces : the development of foreign appreciation of the historic peninsula during two hundred years © The volume is rich in varied interest for the student of European culture. e is a work of research representing a vast to anyone who desires to follow the story of moderi amount of reading and labor, and will be of service culture and intellectual life—The Dial. Old German Love Songs: Translated from the Minnesingers of the 12th to 14th Centuries | By FRANK C. NICHOLSON 236 pages, 8vo, cloth; net $1.50, postpaid $1.61 In this volume an attempt has for the first time been made to present English readers with a fairly large and typical selection from the German Minnesingers of the twelfth to the fout- teenth centuries. The English versions, while preserving the form of the originals, aim, 50 far as is possible, at faithfulness of rendering. An introductory essay discusses the naturt and history of Minnesong. Professor Edward Dowden writes: The introduction and the translations have given me true enjoyment. THE UNIVERSITY OF CHICAGO PRESS First Year Mathematics for Secondary Schools By GEORGE WILLIAM MYERS, Professor of the Teaching of Mathematics and Astronomy in the College of Education of the University of Chicago. Assisted by the Instructors in Mathematics in the University High School. 198 pages, 12mo, cloth; net $1.00, postpaid $1.09 The object of this new course in mathematics is to do away with the present artificial divisions of the subject and to give it vital connection with the student’s whole experience. The first year of secondary work is devoted (1) to generalizing and extending arithmetical notions, (2) to following up the notions of mensuration into their geometrical consequences, and (3) to reconnoitering a broadly interesting and useful field of algebra. This means postponing the scientific and purely logical aspects of algebra to a later period. Geometric Exercises for Algebraic Solution, for Secondary Schools By GEORGE W. MYERS and the Instructors in Mathematics in the Univer- sity High School go pages, r2mo, cloth; net 75 cents, postpaid 82 cents This book supplies means for holding, through the second year geometry course, the ground made in algebra during the first year. By the use of geometric problems to be algebraically solved the course serves the three-fold purpose (1) of keeping algebraic pro- cedure in continual use, (2) of holding the unity of the geometrical course intact, and (3) of pointing out many connecting by-ways and overlapping districts of the two domains of ele- mentary mathematics. Animal Micrology: Practical Exercises in Microscopical Methods By MICHAEL F. GUYER, Professor of Zodlogy in the University of Cincinnati 250 pages, 8vo, cloth; net $1.75, postpaid $1.88 The title of this book will explain its scope. It is intended as a laboratory manual for textbook use. Its aim is to introduce the student to the technique of microscopic anatomy and embryology, emphasizing details of procedure rather than descriptions of reagents or apparatus. Sufficient account of the theoretical side of microscopy is given to enable the student to get satisfactory results from his microscope. One of the best and most practical works upon A concise, eminently practical, and well-classified microscopic technique with which we are acquainted. treatment.—Science. —American Naturalist. Mir’at az-Zaman (A. H. 495-654), by Sibt Ibn Al-Jauzi: A Facsimile Reproduction of Manuscript No. 136 of the Landberg Collection at Yale University Edited with Introduction by JAMES RICHARD JEWETT, Professor of the Arabic Language and Literature in the University of Chicago 544 pages, 4to, cloth; net $20 00, domestic postage 56 cents This manuscript covers the last 120 years of the history, the period about which the author may be supposed to have known most. No manuscript for this portion exists in Europe. The one here reproduced is in fine condition, and the copy has been pronounced excellent. Per UNIVERSITY OF CHICAGO PRESS The English Reformation and Puritanism, and Other Lectures and Addresses | By the late ERI B. HULBERT, Professor and Head of the Department of 7 Church History in the University of Chicago 352 pages, 8vo, cloth; net $2.50, postpaid $2.71 The late Dean Hulbert was a unique and striking character. Those who knew him] and who enjoyed the flavor of his keen, incisive talk, will be glad to know that a number of his lectures have been collected and published. Many also who did not know him person-7 ally will enjoy the book, and will be impressed as never before with the appalling cost of the civil and religious liberty that we now take as a matter of course. A Genetic History of the New England Theology By FRANK HUGH FOSTER 580 pages, small 8vo, cloth; net $2 00, postpaid $2.19 As the first genetic history of the greatest theological movement which America has7 yet known, the book deserves the attention of all sans of our national thought. Professor Foster has appreciated his ee a gee writings of the aye — is clear and) bestowed upon it the labor and pains which i penetrating.—The Na importance deserves. His peor: of ve work ae The Investment of Truth, and Other Sermons By the late FREDERIC E. DEWHURST, Pastor of the University Congres tional Church, Chicago 174 pages, 12mo, cloth; net $1.25, postpaid $1.37 Mr. Dewhurst was by nature an investigator, keenly sensitive to the more subtle rela- | tions of things. Professor Albion W. Small says of this book of sermons: “‘It is a contribu-_ tion to the literature of strenuous communion with God.” The reading of these sermons confirms Mr. Mr. Dewhurst’s appeal is to ~ Hew; but to thes coe words They are vital, ce deal with the he appeals strongly. —The | Nat ig things of life-—Christian Regi Love and Loyalty By JENKIN LLOYD JONES, Pastor of All Souls Church, Chicago 400 pages, t2mo, cloth; net $1.50, postpaid $1.66 Twenty-three sermons by the noted pastor. With the exception of the introductory discourse, they were all delivered as ‘class sermons” for successive graduating classes, and the text is in every case the class motto. The collection thus represents a cross-section o a quarter century from a busy city ministry. Composed for boys and girls, the discourses should appeal particularly to others of like age, but anything that appeals to the young interest5__ their elders likewise. The book is therefore issued in the belief that many will find a value- in the noble ideals here set forth. THE UNIVERSITY OF CHICAGO FRESG BOOKS IN PRESS The Witness of the Oriental Consciousness to Jesus Christ By CHARLES CUTHBERT HALL, President of Union Theological Seminary. A profound impression was made by this author’s Christian Beliej Interpreted by Christian Experience. The many readers of that volume will be glad to know that a work on a closely related subject is soon to be issued. Descriptive Geography of Palestine By PROFESSOR LEWIS BAYLES PATON, of Hartford Theological Seminary 96 pages, 8vo, cloth Recent residence in Jerusalem and a thorough study of the literature, Voth ancient and modern, have qualified the author of this little volume to write interestingly and authori- tatively on the topography and archaeology of the Holy Land. The facts as presented are precisely those which the student of the Bible needs to know. The book will be fully illus- trated, and will constitute a notable contribution to the subject. Sidelights on Biblical Chronology, Part 1 By OLAF A. TOFFTEEN, Professor of Semitic Languages and Old Testament Literature in the Western Theological Seminary 250 pages, 8v0, cloth This is an examination of the data furnished by the monuments bearing on biblical his- tory, and constitutes an elaboration of the first chapter in Ancient Chronology. While it would be perhaps too much to say that Dr. Toffteen reaches conclusions altogether new, he has displayed the same independence of research and reasoning which characterizes his treat- ment of the broader subject of ‘“‘ancient chronology.” ‘The result is an able, fearless, and scholarly statement of views concerning historical data of the Bible. Value and Distribution By HERBERT J. DAVENPORT, Assistant Professor of Political Economy in the University of Chicago 500 pages, 8vo, cloth The Process of Government: A Study of Social Pressures By ARTHUR F. BENTLEY 432 pages, 8vo, cloth After a general discussion of sociological principles the author elaborates a theory in which “social pressures”—i.e., the stresses exert y the various social elements— are treated as a basic factor. The work is not intended for the general reader, but to the specialist it will be of the deepest interest. Poe USNTVERSTIIY OF: CHICAGO PRES@ CONSTRUCTIVE BIBLE STUDIES RECENT ADDITIONS Child Religion in Song and Story By GEORGIA L. CHAMBERLIN anp MARY R. KERN Teacher’s Manual, $1.00 Pupils Notebook, 40 cents In the planning of the course, it has been assumed that the first, second, and third grades (ages six to eight) will meet in one room. The opening and closing portions of the service _ are placed in charge of a single leader, but for the more detailed study and the manual work © the children are divided into “groups” of six or eight each in charge of a teacher. Detailed _ directions are given for the entire programme of each Sunday, and all necessary material is supplied. The Life of Jesus By HERBERT W. GATES Teacher’s Manual, 75 cents Pupil’s Notebook, 50 cents An attempt has been made to furnish a course that shall give occupation for hand © and eye as well as for brain, that shall be sufficiently varied in treatment to sustain inter-_ : est, and that shall result in a clear, vivid conception of the life and character of Jesus Christ, ~ so far as these may be grasped by pupils of twelve and thirteen years. The test already © given these lessons has proved that such results can be secured through intelligent use. Christianity and Its Bible By HENRY F. WARING, Pastor of the Brussels Street Baptist Church, Halifax, Nova Scotia 389 pages, 8vo, cloth; postpaid $1.00 This book contains in twenty-three chapters a sketch of the origin of the Old Testa- ment religion and of Christianity, a history of the Christian Church, and a summary of | present-day Christianity. It is both a trustworthy and a useful book, well adapted to increase religious intelligence —T he Outlook The New Appreciation of the Bible: A Study of the Spiritual Outcome of Bible Criticism By WILLARD CHAMBERLAIN SELLECK, Pastor of the Church of the Mediator (Universalist) Providence, R. I. Author of The Spiritual Outlook 424 pages, 12mo, cloth; net $1.50, postpaid $1.63 The book seeks to do three things; first, to state, briefly but clearly and accurately, the principal conclusions of modern learning regarding the Bible; second, to show the enhanced values, ethical and religious, which the Bible exhibits through the new views of its nature thus developed; and, third, to point out some of the practical ways in which it may be most fe helpfully used in consonance with such conclusions and such views. A better book for “thoughtful Sapery generally Readers of his careful chapters will have little to who really want to know the trut ant w ‘can hardly be unlearn if they pursue their studies further.—T7he _ found.—Christian Register. N ation. ; LHE UNIVERSITY OF CHICaGOC FRE aa CONSTRUCTIVE BIBLE STUDIES The spete tent Bible Studies are the outgrowth of the conviction that the prevailing systems of Sunday-school instruction are insufficient to meet the growing demands of the times. Believing the Sunday school to be the great educational branch of the church, the editors have sought to produce a series of religious textbooks, based on the fundamental laws laid down by trained educators. One of the most important of these laws is the principle that the curriculum must be adapted to the capacity of the pupils, giving to each grade work which is suited in material and method of treatment to the stage of develop- ment of the pupils. The studies comprise four series, each corresponding to a definite stage of development in the pupil. KINDERGARTEN SERIES One Year of Sunday-School Lessons By FLORENCE U. PALMER Postpaid $1.00 ELEMENTARY SERIES Child Religion in Song and Story By GEORGIA L. CHAMBERLIN anp MARY ROOT KERN Teacher's Manual, postpaid $1.00 Pupil’s Notebook, postpaid 40 cents An Introduction to the Bible for Teachers of Children By GEORGIA L. CHAMBERLIN Postpaid $1.00 The Life of Jesus By HERBERT W. GATES Teacher's Manual, postpaid 75 cents Pupil’s Notebook, postpaid 50 cents SECONDARY SERIE Studies in the Gosp2] According to Mark By eae DEWITT BURTON Postpaid $1.00 The Life of Christ By ERNEST DEWITT BURTON anp SHAILER MATHEWS Postpaid $1.00 A Short History of Christianity in the Apostolic Age By GEORGE H. GILBERT Post- paid $1.00 ADVANCED AND SUPPLEMENTARY SERIES The Priestly Element in the Old Testament By WILLIAM RAINEY HARPER Post- paid $1.00 The Prophetic Element in the Old Testament By WILLIAM RAINEY HARPER Post- paid $1.00 A Short Introduction to the Gospels By ERNEST DEWITT BURTON Postpaid $1.00 A Handbook of the Life of the Apostle Paul By ERNEST DEWITT BURTON Post- paid 50 cents Christianity and Its Bible By HENRY F. WARING Postpaid $1.00 HELPS FOR SUPERINTENDENTS AND TEACHERS Principles and Ideals for the Sunday School By ERNEST DEWITT BURTON anp SHAILER MATHEWS Postpaid $1.11 An Outline of a Bible-School Curriculum By GEORGE W. PEASE Postpaid $1.65 Hebrew Life and Thought By LOUISE SEYMOUR HOUGHTON Postpaid $1.65 The New Appreciation of the Bible By WILLARD C. SELLECK Postpaid $1.63 [The following volumes will be ready shortly.] The Life of Christ: an adaptation of the book by Burton and Mathews, for pupils of the ae hie school age rie ISAAC BRONSON BURGESS Studies in Samuel By HERBERT LOCKWOOD WILLETT 788 UNIVERSITY: OF CHICAGO FRE PUBLICATIONS IN SERIES Attention ts called to the ieee series, for which we are publishing agents. Full injor- mation will be sent on reques. gears in Biblical Archaeology: A Series of Volumes Dealing h the Chronology, Geography, Social and Religious Insti- ee Art and Literature of the Biblical Nations By OLAF A. TOFFTEEN, Professor of Semitic Languages and Old Testament Literature in the Western Theological Seminary. Published for the Oriental Society of that Institution. ; [Now ready.] Volume I, Ancient Chronology, Part I: From 3400 to 1050 B. Cc. 300 pages, 8vo, cloth; net $2.50, postpaid $2.70 As a preliminary to a detailed treatment of biblical chronology, the author undertakes in this volume a survey of early chronology in general in the light of the latest researches in Babylonian, Assyrian, and Egyptian history. His conclusions are in many respects at variance with those of a recent scholars, and tend to support the authenticity of the Old Testament narrative. The following volumes are in preparation: Sidelights on Biblical Chronology, Part I Ancient Migrations, Part I Ancient Chronology, Part II The pi oaarae of Philosophy in the University of Chicago announces the publica-_ tion of a series of monographs under the foregoing title, to include the subjects of ethics, : logic and Eaeae tag a and the history of philosophy. The initial number is ready* The Ethical Significance of Feeling, Pleasure, and Happiness in —— Non-Hedonisti¢ Systems. 98 pages, Svo, paper; net 50 cents, postpaid 54 cen : By WILLIAM KELLEY WRIGHT Philosophic Studies . [In preparation. ] The Respective Standpoints of Logic and Psychology By MATILDE CASTRO Publications of the National Society for the Scientific Study rq Education (formerly the National Herbart — : on application. The ¥ Yearbooks ia 180 sii and for 1902-1906 have been oat net. THE “GNIVERS{ ITY OF CHIiCAGCGe FREiso Publications of the American Sociological Society Vol. I. Papers and Proceedings of the First Annual Meeting, Held at Providence, Rhode Island, December 27-29, 1906 148 pages, 8vo, paper; net $1.50, postpaid $1.56 Contents: The American Sociological Society The Establishment of Sociology. By Lester F. Ward How Should Sociology be Taught as a College or University Subject? By Charles A. Ellwood Western Civilization and the Birth-Rate. By Edward A. Ross Points of Agreement Among Sociologists. By Albion W. Small The Fine Arts as a Dynamic Factor in Society. By Mrs. J. Odenwald-Unger Social Consciousness. By Charles H. Cooley Social Darwinism. By D. Collin Wells Constitution of the American Sociological Society List of Members DISSERTATIONS Under the regulations of the University, doctors’ theses must be printed. It is frequently of advantage to the writers to have their productions published, and many candidates employ the University Press for that purpose. Students of other institutions also are beginning to avail themselves of the special facilities of the Press for this class of work. Some recent issues are: The Infinitive in Polybius Compared with the Infinitive in Classical Greek : Being Part IV of Vol. I of Historical and Linguistic Studies in Literature Related to the New Testament. 60 pages, 8vo, paper; net 50 cents, postpai By HAMILTON FORD ALLEN The Deification of Abstract Ideas in Roman Literature and Inscriptions. 102 pages, 8vo, paper; net 75 cents, postpaid By HAROLD L. AXTELL Decimus Junius Brutus Albinus. 114 pages, 8v0, paper; net 75 cents, postpaid 80 cents By BERNARD CAMILLUS BONDURANT The => the Mayewpo: in the Life of the Ancient Greeks. 1oo pages, 8¥0, paper; net $1.00, post- id $1.0 By EDWIN MOORE RANKIN The So-Called Rule of Three Actors in Greek Classical Drama. 88 pages, 8v0, paper; net 75 cents, By KELLEY REES The General Civil and Military a of Noricum and Raetia. 7o pages, §vo, paper; net 50 54 cents. ts, By MARY BRADFORD PEAKS TEE UNIVERSITY OF CHICAGO PRES PERIODICALS THE So WORLD Ernest D. Burton, Editor in Chief. Published monthly, Shag illustrations. Subscription price, 2.00 a year, sia copies, 25 cents; foreign postage, 68 c THE SCHOOL REVIEW | oN, by the Department of Philosophy and Education of the University of Chicago. Published” onthly, except in — and August. Subscription price, $1.50 a year; single copies, 20 cents; saetion postage, 52 ce THE ELEMENTARY SCHOOL TEACHER Edited by the Faculty of the Elementary School of the University of Chicago. Published noo A except in July and August, — illustrations. Subscription price, $1.50 a year; single copies cents; foreign postage, 46 ce THE BOTANICAL GAZETTE Edited by JoHN M. CouLrer and CHAR . BARNES. Published ip ayant = illustrations. — Subscription ag $5.00 a year; single anen e cents; foreign postage, 84 ce THE JOURNAL OF oe Edited by peptone AS C. CHAMBERLIN. Published semi-quarterly, — illustrations. Subscription] price, $3.00 a year; te copies, 50 cents; Panacis postage, 53 cen 4 THE ASTROPHYSICAL Ureselits Edited by Georce E. Hate and Ep . Frost. Published monthly, except in February and pata with idiots Siksceipeis. eee. $4.00 ayear; single copies, 50 cents; foreign postage 62¢ THE AMERICAN JOURNAL OF SOCIOLOGY Edited by ALBION W. SMALL. seein, bimonthly. Subscription price, $2.00 a year; single copies, 50 cents; foreign postage, 43 ce THE JOURNAL OF POLITICAL ECONOMY Edited by the Faculty of Political Econom my of the University of Chicago. Published monthly, exce in Sag and September. Subscription price, $3.00 a year; single copies, 35 cents; foreign postag 42 THE pemeee JOURNAL OF THEOLOGY Edited by the sos Faculty of the tna of Chicago. Published quarterly. Subscriptio price, $3.00 a year; single copies, $1. 00; foreign postage, 41 cents THE eee JOURNAL OF SEMITIC LANGUAGES AND — Edi RT FRANCIS HARPER. a quarterly. Subscription price, $4.00 a yea single copies, $1. -25; foreign postage, 26 ¢ MODERN Pista) bate Edited by Puinre S. ALL N, FREDERIC I. CARPENTER, and JEFFERSON B. FLETCHER. Soageae quarterly. Sitectipticis are $3.00 a year; single copies, $1.00; foreign postage, 41 cen THE CLASSICAL Apaiis Edited by Gorpon J. Lainc and ARTHUR G. Lairp. Published monthly, except in Jul August, ys poor and Oecken Subscription price, $1.50 a year; single copies, 25 cents; foreig postage, 24 CLASSICAL pel cee Edited by the Classical Faculties of The University of Chicago. price, $2.50 a year; single co copies, 75 cents; foreign postage, 23 ¢ THE UNIVERSITY RECORD Edited by the Recorder of the University of Chicago. Published quarterly. Subscription prices $1.00 a year; single copies, 25 cents; foreign postage, 16 cents, oe quarterly. Subscriptio ITALIAN BOOKS of every description FRANCESCO TOCGI, 520 Broadway, NEW YORK. Works of: Barrili, =e Caccianiga, Capra nica, Capuana, Carduc Castelnuo age Cor- delia, D’Annunzio, o Amicis, De Marchi, Farina, Fogazzaro, Giaco: egri, Praga, Rovetta, Serao, and po ‘csaien cman always on han Catalogue mailed on application. FOREST SERVICE Bobi ire SARGENT’S: SILVA OF NORTH AMERICA Cost $350.00 net ; oe of books on TRY AND BOTANY press W.WLA THE ASTROPHYSICAL JOURNAL Issued monthly except Feb ary and Augus single copies 50 cents. fetes < 62 cents. WASH NGTON, D.C. | Shows $4.00 a year; Che Unibersity of Chicago press Ce AND 1 sige Toe ESLEY & SON, INDO College Use — Lip ag aps? free of duty a from 35 to 40% Sie the rican prices. We oe microscopes s for the largest institutions in the for gr ests on the screen opaque objects, and lantern book illus eevee engravings slides, is the most perfect instrument of its kind. It has a “Aelnelé able Book-Holder. Concentrates. all light on the object. Paeac matter corre caked Ae histo weet Botany, pont and sient sciences. Lists o spp ‘BROWN & EARLE, Dept. be 918 Chestnut St., Philadelphia, Pa. -— ES eRe eis Soke Yen, Rate Vote ne ks eee, A LABORATORY GUIDE IN BACTERIOLOGY By PAUL G. — EMANN, Fellow in Bacteriology University of Chicago. pages, interleaved, with 37 illustrations, 158 pa: t2mo0, cloth; net $r. 50, postpaid $r.6r clear and concise presentation = ged nci ers in the fields of medicine and hyg ** The —— given is clear and accurate, and th year net exercises are well selected.”’—7he bance (London ** A book a as this must facilitate very greatly the practical class baer for — it is most excellently adapted.”—A merican Journal of Medtcail Sciences, “ The directions are clear and concise, » and every stage nat i : oa the student can go astray. Physicians who are rusty u tle bo oe "— American Journ Bre Clinical Medic cine, THE emiversir¥ OF CHICAGO papi CHICAGO AND NEW YOR CG. H. STOELTING C0. 31-45 W. RANDOLPH ST., CHICAGO Botanical Apparatus and Supplies for Morphology, Physiology, Ecology SPECIALTIES Potometer, Clinostats. Auxometer, Cases, Clement’s ‘aeiuenink, eee cod Big aa oal Re the te a Important Books on Botany PLANT ANATOMY From the Standpoint of the Development and Functions of the Tissues, and Handbook of Micro-Technic By WILLIAM CHASE STEVENS * Professor of Botany in the University of Kansas. With 130 Illustrations. Octavo; 349 pages. /Just Ready. Cloth, $2.00 net. VEGETABLE PHYSIOLOGY An Introduction to the Subject. By J. Reynotps Green, Sc. D., F. L. S., F. R. 5S. Late iene of Botany. in the Pharmaceutical Society of Great Britain; sabi Scholar of ity College and Senior Demonstrator in Physiology, University of Ca lage Second nae Revised. 182 Illustrations. Octavo; 459 pages. /ust Ready. Cloth, — th, ———. ORGANIC MATERIA MEDICA AND PHARMACOGNOSY An Introduction to the Study of the Vegetable Kingdom and the Vegetable d Animal Drugs. By Lucius E, Sayre, B.S., Ph. M. Professor of Materia Medica and Pharmacy in the University of Kansas. Third Edition, Revised. With 377 Illustrations. Octavo; 692 pages. Cloth, $5.00 met. Sea ES MEDICINAL PLANTS OF THE PHILIPPINES By T. H. Parpo De Tavera Doctor of Medicine in the Faculty of Paris; pr eaes Commissioner S. M. in Philippine Islands, ete. Translated and Revised by Jerome B. Thom ee A. B., M. D., Captain and Assistant Surgeon, United States erase I2mo; 268 pages. Cloth, $2.00 met. P. BLAKISTON’S SON & CO., Publishe 7 Biological, Medical, Chemical and Allied Scientific Books -tor2 WALNUT STREET, ae i PHILADELPH AS a Ae Cr SE Bt Ne A Blt ee OO te aide Ba a Ac 6a ee eg A aad nes ee A cn es aaa eae a bee a We oh ee eae ee PT Rich ee nner sek te VOLUME XLV NUMBER 1 BOTANICAL (GAZETTE JANUARY 1908 . SPOROGENESIS IN NEPHRODIUM CONTRIBUTIONS FROM THE HULL BOTANICAL LABORATORY 106 SHIGEO YAMANOUCHI (WITH PLATES I-IV) - Historical review There have been published during the past three decades a few accounts of sporogenesis in pteridophytes. Since cytological studies have advanced rapidly in recent years, many views which were once prevalent have been proved to be erroneous, or at least to be capable of a different interpretation, and the authors themselves may have at present entirely different views from those which they held when the accounts were published. It seems worth while, therefore, to make a historical review of some of the work hitherto published. There is first a paper by HumpHREY (29) on the study of the spore —— Osmunda, Psilotum, and other forms, in which the main purpose was to prove the presence of extranuclear centrosomes in pam above the bryophytes. His account of the number of chromosomes in Osmunda was taken up by a cit in his data dealing with the periodic reduction of in the life-history of organisms, as one of the instances hike prove the constancy of the number of chromosomes in a certain period of the life-cycle. OsTERHOUT’S (35) studies on Ronicoics sane ually de vt the most important contributions to our knowledge of the spore mother Ez 2 BOTANICAL GAZETTE [JANUARY common axis, but the poles of the spindle at metaphase hold their composite nature with entire absence of the focal center or centro- some. This account, which did much to dispose of the current idea that the development of the spindle in higher plants is controlled by centrosomes, is noteworthy. Then appeared two papers with detailed description of the method of division and distribution of chromosomes: one by CALKINS (11) on Pieris tremula and Adiantum cuneatum; and the other by STEVENS (44) on Pieris aquilina, Cystopteris jragilis, and Scolopendrium vulgare. CALKINS believed that there was a tetrad formation of chromosomes in the prophase of the spore mother cell of ferns, and that the process of sporogenesis in those forms followed the same course as was observed in the maturation division of sexual cells in animals, with a transverse division and consequently a qualitative reduction in WEISMANN’s sense. STEVENS’ studies on the forms named above disagree with Carns’ view in several particulars, the main point being that there is present no transverse division of chro- in the spore mother cell, but two longitudina divisions, and therefore there is merely a quantitative reduction. Stevens’ observa- 4 rogenesis of Osmunda regalis. HOUT in regard to the absence somes, and differ as to the origin and development of the spindle; he held that the spindle was bipolar from the beginning. of the spindle of the 1908] YAMANOUCHI—SPOROGENESIS IN NEPHRODIUM 3 and that he agrees with the views maintained by FARMER and Moore (18), GREGorY (26), and STRASBURGER (49). CARDIFF’s (12) studies of synapsis and reduction in several forms of flowering plants and in Botrychium obliquum paid particular atten- tion to the formation of the spirem and its behavior up to the forma- tion of bivalent chromosomes in the heterotypic mitosis. According to him, paired threads, which appear in the presynaptic stage of the nucleus, fuse during synapsis and again split longitudinally after synapsis, probably along the line of the previous fusion. In 1907 a paper entitled “Studies in apospory and apogamy in ferns” appeared under the joint authorship of Farmer and DicBy (16), whose two preliminary notes were published in 1903 and 1905. This paper deals directly with the matter indicated by the title, but some stages in the division of the spore mother cell are déectibed in three forms of Lastrea and one species of Scolopendrium. The paper is accompanied by many important figures, but only three of the spore mother cells with heterotypic chromosomes are given, so far as sporogenesis is concerned. Recently there appeared two papers, one by BURLINGAME (10) on Ophioglossales, and the other by GréGorIRE (24), with the title “La formation des gemini hétérotypiques dans les végétaux.” BuR- — LINGAME’S paper is chiefly devoted to a study of the sporangium. From the cytological standpoint Gr&GorRE’s paper is very important. His views, which were published in 1904 (25), concerning the structure of the resting nucleus of the spore mother cell, interpretation of synap- sis, formation of chromosomes of the heterotypic mitosis, and distri- bution of the daughter chromosomes in the first and second divisions, __were based chiefly upon BERGH’s studies (6, 7) of Allium, Lilium, and other forms; but in this recent paper Gricorre records the _ results of his own ———e—S— cotyledons, which iors his previous views. ‘ BOTANICAL GAZETTE [JANUARY be regarded as introductory to a paper entitled “A study of apogamy,” — which will appear later. Much attention has been paid to the behavior — of chromosomes, combining observations with theoretical views, with — a hope of securing an explanation of the phenomena obaeeved: so that the chromatin substance will be the chief object treated in the — present paper. I wish to express my gratitude to Professor JoHN M. CouLTER © and Dr. CHARLes J. CHAMBERLAIN for their kind advice and criticism _ during the progress of this work. I am also under obligation to other — members of the botanical staff for courtesies extended to me. MATERIAL AND METHODS The material for this investigation was collected in greenhouses — of the Hull Botanical Laboratory, and in Lincoln and Washington — parks, Chicago, from October 1906 to March 1907. 4 Killing and fixation were made in various fluids, among which FLEMMING’s weak solution, with a little modification in the percentage of acetic acid, proved most effective. The material was left in the — fluid for two to four hours, then transferred into fluid of the same _ formula, but without osmic acid, ten to twenty hours. The thoroughly washed material was passed very carefully through ~ _ @ series of alcohols b Deeg St WE Pet cent... wn. imbedded : : plat al wicras The sections were cut 3-s » in thickness and _ in gentian n-violet, or iron-alum-hematoxylin, some- stains, such as safranin, orange G, eosin, — : or Congo red. Alcea. etn ¥.56°" NLA. .30, 7 laa pias ie eo a at i i a Set gay lis 5 i i a i i kt es Se ee a compensating oculars were used for studying the preparations. scription - By er ere Bea ert ae ee Ee Rec Rare ae _ siete te _ A leaf too your es sori shows in its various parts the suc- a cone sags mitosis. The form of the mitotic figure is a ies in the size of the cell which contains it, and — oe a the dig of shiek: oil, and other cell contents interferes some- - : : aos with accurate ss The mitotic figures which occur — 1908] YAMANOUCHI—SPOROGENESIS IN NEPHRODIUM 5 most favorable, being entirely free from such obstructions, and these mitoses will be used for the following description. 3 The resting nucleus in the sporogenous tissue contains a chromatin reticulum with one or several nucleoli. The general structure of the nuclear reticulum needs mentioning. It does not seem to consist of two distinct elements, chromatin and linin, with chromatin granules distributed irregularly upon or imbedded in the linin ground-sub- stance, but it seems to be composed entirely of chromatin material. The appearance which indicates that there may exist a mixture of two substances—the dark-stained masses and light-colored strands— does not seem to be due necessarily to a different affinity for stains, but to the fact but that the more compact regions of chromatin material are more affected by stains than the more loosely aggregated regions, which are lightly stained. The number of nucleoli is variable and there seems no rule for their position in the nuclear cavity, for sometimes they lie very close to the membrane and sometimes they are centrally located. The form is rounded in most cases, but often they are aggregated into one or two irregular masses. Even in the resting nucleus they show a vacuolized structure. tributed, often great masses being located in the center or sometimes eccentric near the periphery, leaving the center vacant. Approach- ing the prophase, there seems to be a tendency of some of the chroma- tin material to form a continuous spirem, i. e., some fine strands of the chromatin may break apart — or ow become thicker by getting the material from some ragged ¢ n clumps oe gradually uniform in thickness and Beco Fok igi ors 4 ] cavity (fig. 1). Whether there is present a single spirem or not was not determined. Close examination of this stage in a number of preparations showed that it was hardly possible to make out free ends, ee eS SS the chromatin tum, sth hey nt sem 1 come | eS Usually at this stage they se 6 BOTANICAL GAZETTE [JANUARY While these events are going on within the nucleus, there are formed kinoplasmic caps at two poles outside. The kinoplasmic cap at first consists of a few fibers arranged in a cone, the fibers evidently running in a longitudinal line, one end focusing at one pole, and the other end diverging toward the nucleus, reaching nearly to the nuclear membrane or falling short of it. Since no change ever occurs in the nuclear membrane, these fibers certainly originate from the rearrange- ment of the cytoplasm where the cone arises.. The whole cytoplasm, except where the kinoplasmic caps arise, shows at this time a fine fibrillar structure. Now the nuclear membrane begins to disappear at the basal region of the kinoplasmic caps, the rest of it still clearly limiting the nuclear contents from the cytoplasm outside. There seemed to be no regularity in the course of the spirem until this stage. _ The entangled spirem was distributed throughout the cavity, the bent parts of the loops being directed toward the membrane; but when the nuclear membrane begins to disappear near the kinoplasmic caps, some parts of the spirem seem to move out in the direction of the _ a; Then follows the entire disappearance of the nuclear membrane, = segmentation of the spirem into a certain number of slender : osomes ». aod the intrusion of spindle fibers which become Ss ae 2). At this time there — an LI in: ! 7 ee the two poles; oie exul yeaches near the pele. and about the equatorial region lies the other end, to which spindle fibers from the two opposite _ poles a are a ‘so that the distance of the attached ends from — pproximately the — of two chromosomes. This — ‘the c — shown in fig. pee chromosomes : — apa ses st tation to this peri 1, now begin to shorten; — ds, to which the sade fibers from the t two 0 poles are a: a, es ee 1908] YAMANOUCHI—SPOROGENESIS IN NEPHRODIUM 7 shortening, a stage such as that represented in jig. 4 has been described by some authors as being a typical figure of vegetative mitosis in ferns. However, the shortening of the chromosomes proceeds still farther, until the bent ends lying at the equatorial region become straightened, and the chromosomes become rod-shaped; thus there is established the stage in which the chromosomes are arranged in an equatorial plate (jig. 5). The two daughter chromosomes formed by the longi- tudinal splitting of a single one at prophase have remained side by side and have been affected equally by the process of shortening, so that now they are almost similar in size and form. When this stage of the equatorial plate is attained, the two daughter chromosomes seem to begin to separate at once. This stage is less frequently met than the earlier or later stages, even in material favorably fixed and showing an abundance of stages. The separation of many daughter chromosomes generally begins and proceeds simultaneously, but rather rare instances are observed of several tardy ones, which separate after their associates are already on tlie way toward Hie’ poles. The chromosomes arranged in the equatorial plate are perfectly s straight; the separation of the two halves begins at the ends where the spindle fibers are attached and proceeds toward the other end, necessarily causing represented in jig. 6; but soon aiter is caveiibels wipaitation they resume their straight form and so persist. When the two sets of daughter chromosomes reach nearly to the poles, they become per- fectly parallel, without overlapping (jig. 8), and in the more favorable cases they are as regularly placed as if they stood in one plane, a stage which is the most satisfactory for counting. The polar view of this stage (fig. 9) shows that the number of chromosomes is 128 or 132. During prophase and even metaphase the number of chro- | mosomes could sometimes be estimated, especially in the polar view at the equatorial plate stage, but not with such exactness as in the page Sct dat the p care Sa arage: | as. 4 at. y together that teed ovr he pol become carta he ns ce 8 BOTANICAL GAZETTE [JANUARY begin to be vacuolized, i. e., chromatin materials which constituted the chromosomes in their compact condition become localized in an irregular way, in some places becoming quite loose, and in others still remaining as a dense aggregation. All the chromosomes undergoing this change are associated, the ultimate result being a vacuolized mass of chromatin material from all the chromosomes (fig. 10). By the interaction between the cytoplasm which surrounds these vacuolized masses and nuclear sap which may be secreted within the vacuolized region of the chromosomes, there is formed a nuclear membrane. As the nuclear sap increases in amount, the nucleus grows in size (jig. rz). The polar end of the daughter nucleus at the time of the formation of the membrance is always concave (fig. 12), very likely due to the — fact that before the vacuolization the face ends of daughter chromo- somes pointed to the pole are drawn together toward the pole so as to come nearer, and that in this position vacuolization has proceeded. It seems probable that the vacuolization is more pronounced in that concave region than elsewhere, so that in the young daughter nucleus | the chromatin material is rather scanty at the region of the previous — pole, where immediately after the organization of the daughter nucleus one or two new nucleoli appear (fig. 13). It may turn out that the daughter nucleus thus reconstructed shows polarity. ft = ss ae ee e. uf 41. 4 ry | 2k with the daught lei there appear granules in an equatorial plane upon fibers of the central spindle. part of the equatorial plane and then toward the periphery. It _ Seems reasonable that the fiber substance has contributed the material _ for the formation of the granules. | _ Contempor: y with the completion of the cell wall, growth of the : d: ugh ter D : cl eee. tit ues : a th ch Yi : tin material ; oo a ragged structure on account of further continuation of vacuolization. ae The general outline of the daughter nucleus becomes nearly spherical division from the reticulum of the resting tio’ of + i - ! stir LU . ee : ction 1908] YAMANOUCHI—SPOROGENESIS IN NEPHRODIUM 9 the sequence of mitosis preceding the formation of the nucleus of the spore mother cell is exactly the same. S porogenesis PRESYNAPTIC STAGE.—The chromatin reticulum in the resting nucleus of the spore mother cell has the same structure as was just described for the nucleus of the sporogenous cell; the size of the nu- cleus, after its full growth, is greater than that of any nuclei of the Sporogenous cells, and not infrequently it occupies almost all of the cell. No regularity could be found in the massing of the chromatin material; at certain points there are dense masses and at others almost none at all. Nucleoli, one to several in number, are always present in various locations, without any physical connection with the chromatin. The exact structure of the chromatin reticulum needs description. It is an anastomosing complex of ragged clumps and irregularly branched strands (fig. 15); the former always stain deeply and the latter lightly, simply because of the difference in compactness of massing. They originated from a single source—the chromosomes of the previous mitosis—by the vacuolization = described above. : The clumps of the reticulum lose gradually their ragged look, clumps to some of the fine strands so as to thicken them (fig. 15a). All these changes tend to transform the ragged structure, but they do not occur simultaneously throughout the reticulum, so the whole is still plainly a reticulate structure, as seen in jig. 16. Nevertheless, in regions where the reticulum is being converted into thread structure there are visibl parts of thr ds 4 ly sid by side (fig. 16a). a Synapsis.—The transformation of the reticulum into a thread _ sracture now proces reply, Loca nas PURO RENY Pl To BOTANICAL GAZETTE [JANUARY show that this loosely tangled mass consists of lightly colored threads and deeply stained granules; undoubtedly the thread in this tangled and contracted condition is not homogeneous throughout; on the contrary, there are present not only irregularities in thickness in parts of the thread, but also the chromatin material is more compact in certain parts and more loosely aggregated in other parts. That the parts of the thread in this stage are double is fairly dis- cernible (jig. 17a) in tangential sections of the nucleus; undoubtedly _ this doubling has come from the changes observed in the earlier stage represented in jig. 16 as originating from the transformation of the reticulum; therefore this double part of the thread cannot be recog- nized as an indication of a new longitudinal splitting, but as two threads independent from the start. These double threads run side by side very closely, as if they were fusing. Whether they are completely fused or not could not be determined, but their association is very close. These masses of threads become more tightly drawn together and contracted into a ball which seems to be the climax of the synaptic stage (jig. 18). FORMATION OF HETEROTYPIC CHROMOSOME s.—The course of the | thread or spirem is irregular in the synaptic stage; it is twisted and _ generally much curled, but there are present several parts of the spirem which run comparatively straight across the contracted ball of the spirem from near the nuclear wall with which it lies in contact. The loops happen to be formed near the periphery of this contracted mass, a ee ene special to do with the formation of : ~~ ts siete of cases the nucleoli seem to unite into one, which _ becomes caught in the tangled mass in the early synaptic stage, gener- y far fro: nie wales membrane, and its spherical form persists. of this stage age shows a rately smooth structure and 2 oe 0 d of . - side by side, often diverging _ ee ater wily 19) IcSems highly probable hat wee he 8 __ indication of the separation of two threads which were first observed : presynaptic sae (ig. 16, 16a) and ¢ Pred nls senepeie, ae 1908] YAMANOUCHI—SPOROGENESIS IN NEPHRODIUM It already described. Now the tangled mass of the spirem begins to uncoil (fig. 20) slowly; superficial parts of the spirem in the synaptic mass at first become widely distributed, while the unraveling of the inner parts of it are naturally delayed, and the longitudinal separation of the two independent parts is observable in the portions of the spirem which are widely uncoiled (jig. 20). The spirem becomes considerably thickened, certainly due to shortening, and becomes distributed loosely through the cavity; while the line of the longitudinal splitting or separation of the spirem into two elements seems obliterated, but its presence is evident in some places (jig. 21). The course of the spirem again becomes irregular, and in some parts there are present complicated tangled masses of the spirem on account of the twisting of the spirem itself, but double threads, the constituents of the spirem, run mostly in close association (jig. 22). Shortening and thickening of the spirem proceeds until it segments into chromosomes. As shown in figs. 23a and 236, the segmentation is not simultaneous throughout the entire spirem, but finally there are formed 64 or 66 chromosomes, each bivalent in nature (jigs. 244, b, ¢). The two halves of the bivalent chromosomes lose their close asso- ciation after their segmentation, and show every possible position and connection with each other, such as H, I,J, K, L,0,T, U,V, X,Y, and so forth, and even give an impression of being of different length and size, mostly due to the point of view. The chromatin material which constitutes the surface region of the chromosomes seems loosely aggregated, but it is compactly massed in the center, and there are observed faintly stained substances of fibrillar form — attached at the ends of chromosomes, which seem to be remnants of the ma srial of the spirem left over at the time of segmentation, aebably oh account of the viscid nature of the spirem. The loosely aggregated chromatin material is gradually drawn and condensed tard the central part, but the condensation procs takes place | | 1 while the ch es appear _ a recontic shuartened, wad: ¢ the loose fibrillar append: : hor iy tn man - me, 7 ae an it been 2 oT See 12 BOTANICAL GAZETTE [JANUARY A short description of the chromatic substance seems necessary. Early in the resting stage of the nucleus, the cytoplasm shows a fine fibrillar structure, almost homogeneously distributed. When the nuclear structure begins to enter into synapsis, long kinoplasmic fibers appear from the Tearrangment of the cytoplasm surrounding the nucleus, but far apart from the nuclear membrane. Between these kinoplasmic fibers and the nuclear membrane there is present a clear region free from any fine fibrillar structure, which was the main feature of the other parts of the cytoplasm before the appearance of the kinoplasm (fig. 21). Some of the stages showing such a process are Tepresented in figs. 21-25. The nuclear membrane, which has stained distinctly, now becomes less and less affected by stains and seems to be dissolved entirely, but for a short time the encroaching and anastomosing kinoplasmic fibers preserve the previous nuclear outline (figs. 25a, b,c). The kKinoplasm, as a rule, surrounds the _ nuclear membrane, but some of the threads run in somewhat radial _ directions. No distinct polar formation was observed. When the kinoplasmic fibers push into the nuclear cavity, some of them are seen to be attached to the chromosomes, while others pass through, and a multipolar structure becomes noticeable (jigs. 26a, b); from the fibers of the m ltipolar spindle there is worked out the bipolar spindle, as indicated in jigs. 27a, b. Shortening of the chromosomes continues always up to this time, so that now there result very short bivalent chromosomes, different in aspect from those in the early prophase. There is no regularity in the position of the chromosomes, which are found on almost all parts of the spindle, yet it is not hard to otice from successive stages, as figs. 26a, b and 274, b, that there is bat the main body of the 1908] YAMANOUCHI—SPOROGEN ESIS IN NEPHRODIUM 13 chromosomes begin to separate; some of them, on the way toward the pole, show a V-shape, the angle being directed toward the pole. This does not seem to have resulted from the bending of one daughter chromosome, because it always remains straight after separation; hence the V-shape may be regarded as resulting from a new longitudi- nal fission of the daughter chromosome, providing for the two grand- daughter chromosomes of the second division. This longitudinal fission occurs only at the end of the chromosome directed toward the equatorial region, without proceeding to the otherend. The two arms of the V come into contact again as the daughter chromosome reaches the pole. As a tule, the sets of daughter chromosomes pass to the poles simultaneously, but there were observed some exceptional cases where some were much delayed (figs. 31, 32); and rarely the irregularity is so extreme that tardy chromosomes are left behind, while their associates are already in an aces condition at the pole (fig. 34). RECONSTRUCTION OF THE DAUGHTER NUCLEI—When the group of daughter chromosomes reaches the pole, each chromosome for a — short time remains fairly straight, which is favorable for counting the chromosomes from the polar view (jig. 35). Then the vacuolization process begins (jig. 36). There is a certain point of difference in detail between this process and that described in the reconstruction of daughter nuclei in vegetative mitosis; the polar ends of the daughter chromosomes do not seem to be drawn together so as to give a concave form, but begin to be vacuolized at once, while in a state of loose association. The vacuolization is prominent along the line of the longitudinal fission of the daughter chromosomes, a line which became obliterated when the chromosomes reached the pole- After the for- mation of the nuclear membrane it is not impossible | ce certain part of the chromatin substance as representing a certain chromosome (fg. 38); oe the vacuiietnn: ene | the telophase of the heter« to return into the ragged chromatin reticulum from which they are ae _ formed, but the reconstruction jee before the individual outline of : . | auptr nucle dos not pss no he eS ae is lost entirely. Therefore, => et 14 BOTANICAL GAZETTE [JANUARY chromatin reticulum in the telophase of the first division, but always — shows the main body of individual chromosomes recognized in Y- shape, notwithstanding the nucleus grows considerably in size after the formation of the membrane. No nucleolus was observed in the daughter nucleus (figs. 40, gr). The nucleus in such a condition is ready for the second mitosis. GRANULAR ZONE DIVIDING THE SPORE MOTHER CELL.— During the nuclear division described above, the cytoplasm generally has a fine fibrillar structure, with vacuoles here and there near the cell wall. When the chromosomes are arranged at the equatorial plate, fibers — running from the poles cross in the equatorial region near the cell wall, where the cytoplasm begins to be transformed into the granules of this stage. After the organization of the daughter nucleus, the granules begin to increase and proceed rapidly toward the center along an equatorial plane of uniform thickness (fig. 38), at first avoiding only the space which was occupied by the central spindle (fig. 39). At last even the middle parts of the central spindle become replaced with or transformed into granules, so that finally the protoplast of the CHROMOSOMES OF HoMOTYPIC DIVISToN.—As described above, laughter chromosomes which ent t. e dauchte 1908] YAMANOUCHI—SPOROGEN ESIS IN NEPHRODIUM 15 occur because of the bending and curving due to their being gathered into the round cavity of the daughter nucleus. As the disappearance of the nuclear membrane approaches, V elements become more distinctly pronounced (jig. 43), some of the fine strands which branched out from V’s disappear, but irregularity in thickness persists and the arms of the V’s end in very slender threads. The general outline of the nucleus up to this time is always flattened, so that the nucleus shows two different aspects according to whether the view is from the pole or equator of the spore mother cell; hence the same mitotic figure of this nucleus, no matter what stage it may be, will always present two different side views, one being always narrower than the other. As the nuclear membrane breaks down, the cytoplasmic fibers enter into the nuclear cavity, where the chromosomes are crowd (fig. 44). The figure of this stage recalls the combined features of both the heterotypic and the typical forms: the chromosomes, long, slender, and curved, with daughter chromosomes in pairs, resemble those of the vegetative mitosis; the achromatic fibers do not construct a cap, but appear multipolar as in the heterotypic case, although they are from the start observed near the nuclear membrane instead of at a distance from it. The two arms of the V’s, which now provide for _ the two daughter chromosomes of this division, are still hanging together at the angle (fig. 44) at which spindle fibers seem to become attached. When the multipolar condition has passed into the bipolar spindle, the angle ends of the V’s, or the ends where spindle fibers are attached, occupy the position near the pole, while the other ends diverge seinen the equatorial region (jigs. 45, 46). The stage resembles that represented in fig. ——— in passing to the stage of the equatorial plate. Gradually the divergent arms of the V’s, or the daughter pair of - bivalent chromosomes ~ = oe draw near to each other | multaneously —_— 8 Th... 2t ees ducmnmmnes; oak consisting of two : ; chromosc ee toward the equatorial region; ws the aimate result, the ends of — ‘torial plane, te er nt are inc oa — oo re of : a o as are arranged in an equa- cs 16 BOTANICAL GAZETTE [JANUARY vegetative mitosis shown in jig. 4. The shortening and thickening of the bivalent chromosomes begin and proceed in similar rate and degree in each member of the pairs, which is always in contact with its fellow (figs. 48, 49). These processes are exactly similar to those which have already been described in the vegetative mitosis. The bivalent chromosomes are finally shortened into straight, rod-shaped chromosomes and become arranged in an equatorial plate (jig. 50). Some of the bivalent chromosomes in this stage of the second division, unlike that of the first division, are slightly above or below the plane of the rest,so that the polar view is not satisfact y for accurate counting (fg. 51). The separation of the daughter chromosomes which constitute the — bivalent chromosomes begins at once. Generally daughter chromo- somes pass in a group toward the pole, but occasionally the separation of the two halves of certain chromosomes is more delayed than the rest (figs. 52, 53). In any event, the daughter chromosomes which — are on the way toward the pole have a straight rod shape, a little more — elongated than they were when arranged in the equatorial plate. When the daughter chromosomes reach the pole they keep for a while ~ a regular and almost parallel arrangement (jigs. 54, 55), which was © advantageous for counting. The number is 64 or 66 (fig. 56). | The group of chromosomes becomes more and more closely aggre- gated (jigs. 58, 59). When the vacuolization begins, the individual _ outlines of the chromosomes are gradually lost, and after the organi-_ zation of the nuclear membrane, which is formed as in the vegetative ‘Mitosis, the growth of the nucleus follows (fig. 60). ___ Simultaneous with the reconstruction of granddaughter nuclei the cell plate is laid down between them, exactly as in the vegetati oe ; oie . ee wie A in a _ fol S (a x ce in th : : 1: u ht ae Pe ee I t senarated x lar zone in the first mitosis. From the cytoplasm — _ 1908] YAMANOUCHI—SPOROGENESIS IN NEPHRODIUM 17 different hemispheres arise before cell plates are laid down between them, so that the protoplast of the spore mother cell in this case be- comes divided simultaneously into four tetrahedral spores. Discussion of cytological phenomena NUCLEAR RETICULUM.—Since the terms “chromatin” and “linin” were given by FLemMInG (21) and by ScHwarz (42) respectively to the substance of the nuclear network which stains deeply and to the substance of the achromatic reticulum, these two substances have been regarded as essential constituents of the nucleus in its resting stage, and it became the general formula in describing the resting nucleus to state that it contains a fine network of linin fibers in which are imbedded chromatin granules. To determine the real nature of chromatin and linin, and to find out the origin and differentiation of these two elements needs special investigation, which is not, of course, the object of the present work; however, the observation of events that occur between the telophase of one mitosis and the prophase of the next gave the writer the follow- ing notion regarding the nature of chromatin and linin, similar to the conclusion drawn by Gr&corrE and WyGAERTS (25). When a group of daughter chromosomes reaches the pole, they are first drawn tightly together, so as to lose, apparently, their seidivd ual outlines. Vacuolization then takes place in this mass, and with the appearance of vacuoles parts of the mass of chromatin substance ome irregularly separated and distributed so as to become trans- formed into a ragged reticular structure consisting of anastomosing, irregular clumps and finer, branched strands. The membrane, which — peroneal recep Sie a EST the — a3 that ses in : oe vacuoles, paws the mass ae = Se cheamat ‘so that it is highly probable that no achromatic structures are included a within the nucleus. The nuclear reticulum of the resting —— - oS nothing but the result of further advancement of the v — eS The 1 new spirem of the ensuing division - formed again — t ee : or me spore mother cell has been er acd many authors, chief 18 BOTANICAL GAZETTE [JANUARY — threadlike strands in the resting nucleus being only a part of the chro- matin substance that has assumed such a structure. REDUCTION OF CHROMOSOMES AND SYNAPSIS.—Since tetrads were first figured by HENKING (28) in the maturation division of an insect, several authors have reported the tetrad formation in various animals — in connection with the reduction of chromosomes. From studies of the — cell, the presence of the tetrads in the spore mother ce was — arise from rings or double rods, parallel or crossed, which resulted from the longitudinal splitting of primary chromatin rods or segments and which break up into four parts (the tetrads), followed by a trans- verse division. An essentially similar mode of tetrad formation was — described by BELAjEFF (5) in Iris and by ATKINSON (4) in Arsaea : and Trillium. : As already described, there is no tetrad formation in Nephro- The nature of ené two successive divisions of chromosomes in ._ sete sta ~. a < — the s ot a gmeeenes of the spirem 1908] YAMANOUCHI—SPOROGENESIS IN NEPHRODIUM 19 tion of chromosomes, and that the chromosomes of the first division result from the loops, separating by a transverse division at the angle of the loops; while the second division is longitudinal. ATKINSON (4) found two different methods in Arisaema and in Trillium; in the former species the first division was transverse, as Drxon and - SCHAFFNER found; while in the latter the second was transverse, as STRASBURGER and Mortier claimed. Among these three divergent views, which claim respectively that there occur two longitudinal divisions, that the first division is transverse and the second longitudinal, and that the first division is longitudinal but the second is transverse, the third was of short dura- tion. The authors (STRASBURGER and Mortrer) who described the existence of such a case changed their opinion and returned to their former view that both divisions are longitudinal, so that there persist only two views, one claiming the presence of two longi- tudinal divisions, and the other claiming that the first is transverse: the former one of these was held by GUIGNARD (27), GREGOIRE (22), Lioyp (31), and others. However, the more recent studies of synapsis have involved very detailed and accurate observations concerning the nature of the reduc- tion division. Some of the investigators mentioned above have changed their views, while others still maintain them, but in both cases a new or modified notion concerning the origin of chromosomes and the nature of reduction division is held. As described before, the nucleus of Nephuiiars* in the presynaptic stage consists of a complex, anas d chromatin reticulum This ragged reticulum shows a tendency to become transform a thread structure, but the process does not occur aes in different regions. When the transformation has taken place, the two parts of the thread are observed running side by side from the fast Secs din nted in figs. 16 and 16aisevidently What w was called “leptonema’ ~ by Wastwarre 5»). aves trans- in a nucleus with a. 20 BOTANICAL GAZETTE [JANUARY the climax of the synaptic stage (figs. 18, 19); these two stages may cover the “zygonema” condition of WINIWARTER. . The above brings the writer to the conclusion that the spirem is of double nature from the outset, probably derived from the paternal and maternal source, as was interpreted by ALLEN (I, 2, 3), GRE- GOIRE (25), Bercu (6, 7, 8, 9), ROSENBERG (37, 38), and CARDIFF (¥2): In preparations stained with iron-alum-hematoxylin and extracted _ so as to obtain a proper differentiation, the paired chromatin threads" of the spirem appear as if consisting of darkly stained granular parts and a lightly colored ground-substance of threadlike structure, but this simply means that they are not of homogeneous thickness; the ne up to.the segmentation of chromosomes, the condition in fig. 18, where the number of parts of the spirem run out of the membrane, may have some significance which 1908] YAMANOUCHI—SPOROGEN ESIS IN NEPHRODIUM 21 described by FARMER and Moore (17, 18, 19), GREGORY (26), FARMER and SHOVE (20), MorrTieR (34), and SCHAFFNER (41). Consequently, the reduced number of chromosome segments of the heterotypic mitosis in Nephrodium are not two sporophytic chromosomes joined end to end, which come to lie side by side by the approximation of the arms of the loops and break apart at the head of the structure; but they are bivalent chromosomes or pairs of sporophytic chromosomes derived from the two threads of the synaptic stage that are always in close association side by side from the beginning, as claimed by ALLEN, BERGHs, and GREGOIRE. Results obtained by MIvAkE (32) in a number of monocotyledons and by OvERTON (36) in a number of dicotyledons accord in general with this description of the mode of formation and separation of heterotypic chromosomes. Although the present account of Nephrodium differs widely from the accounts of FARMER and Moore, GREGORY, STEVENS, and STRAS- BURGER in the interpretation of the synapsis and the prophase of heterotypic mitosis, yet it agrees in one fundamental point, namely, that the first division is heterotypic and separates whole sporophytic chromosomes. Homotypic piviston.—That the chromosomes in the second division in Nephrodium divide longitudinally is in accordance with the vegetative mitosis; however, there exists an essential point of difference between the two cases, namely, in — mitosis the i josomes in last telophase and those of icon se og division, so that | each mitosis is followed by a resting stage, and a line of new longitu- dinal fission of the chromosomes arises in the early prophase of each division; sla 8 vague Se a SS “Rely an ay pt of te be opus th se 22 BOTANICAL GAZETTE [JANUARY According to the count of chromosomes which was made in the telophase of the first division, the daughter nucleus may contain 64 or 66 chromosomes, the reduced number; however, it should be remembered that this is certainly due to the obliteration of the longi- tudinal fission which appeared in the anaphase, and since this early part of the event of the second mitosis is actually initiated in the ana- phase of the first division, the daughter chromosomes should well be considered as bivalent, consisting of two granddaughter chromosomes, although the actual separation is completed in the prophase of the second division. Therefore the homotypic division, in spite of its dependence upon the first division, should be ded rather as a real part of the reduction division, which completes the process initi- ated in the heterotypic mitosis; in other words, the reduction division is initiated in the heterotypic mitosis, but the reduction of the first division is only apparent; the real reduction in the number of chromo- somes is completed in the telophase of the second division. It follows that the first nucleus which contains the reduced number of chro- mosomes is the spore, and consequently the spore marks the starting- point of the new generation, as discussed by GREGOIRE (25). CENTROSOME.—The presence of the centrosome among the pterido- phytes was reported in the spore mother cell by HumPHREY (29) in Psilotum and Osmunda, and by Carxrys (11) in Adiantum and — Pteris. OSTERHOUT es denied the presence of the centrosome in the spindle formation of Equisetum. __ In Nephrodium, the spindle always arises from the rearrangement : = LR Insp orogenesis. of the nuclear mem- es are. arranged in the <—F 1908] YAMANOUCHI—SPOROGEN ESIS IN NEPHRODIUM 23 in connection with the blepharoplast in pteridophytes will be discussed in the next paper, which will deal with gametogenesis and fertiliza- tion in Nephrodium. UNIFORMITY IN THE NUMBER OF CHROMOSOMES.—STRASBURGER’S paper (46) entitled “‘The periodic reduction of the number of the - chromosomes in the life-history of living organisms,” which was the first enunciation of the significance of sporogenesis and the reduction phenomena in relation to the alternation of generations in plants, was based upon the discovery that there is a uniformity in the number of chromosomes in certain phases of the life-history of the individual. Evidence seems to be accumulating from different groups of plants confirming the notion of constancy in the number of chromosomes in individuals under normal development, although:there are instances where different authors report different counting. Generally speaking, accuracy in counting the chromosomes depends upon the number and form of the chromosomes in the individual under consideration. When the number of chromo- somes is large and their form is slender and curved, accurate counting is naturally difficult. In Nephrodium the writer found this difficulty, due to the great number and curved form of the chromosomes, but it was not impossible to make reliable counting by using certain stages in which the chromosomes assumed a straight rod shape and a regular arrangement, characteristic of this species. In sporogenesis there are three conditions favorable for counting. First the prophase after the segmentation of the spirem into chromosomes, up to the stage just before the disappearance of the nuclear membrane, was favorable — It might well be expected that two parts of the same which happened to be —s cal 1 3 4h eninted nimber BE Shag 4 - SCcCLiONns OF : and this , ssstemy tetartnrer ery Nevertheles co cS cic mh ag tvs ps nda esis _ least number of ct ometin only two, as was given | fer eet nk ond condition good for accu- bet 24 BOTANICAL GAZETTE [JANUARY prophase previous to the disappearance of the membrane is not good — for counting, because of the curved and twisted nature of the chromo- — somes. The polar view of the late prophase or early metaphase is favorable for gross estimation, but in a certain critical stage of late _ anaphase, when the chromosomes are in irregular arrangement at the pole, accurate counting is always possible. . From the counting made in the stages mentioned above, the writer — believes that there is a constant number of eeicionan in Ne- phrodium, i.e., 128 or 132 in typical mitosis and 64 or 66 in the reduction division; the result is evidently not in harmony with the. conclusion drawn by FARMER and Dicsy (16) in their recent paper- The reason for the presence of two sets of numbers of chromosomes (such as 64 or 66) has not been determined. Conclusion Since this study of sporogenesis was carried through as preparatory for the study of apogamy in Nephrodium, the general conclusions ba — in the final paper. Two points, however, may be s : (1) there is uniformity i in the number of siiineciend in the etal and (2) in the normal life-history there is a reduction of chromosomes in sporogenesis. _ THe Untversiry or CHIcaco LITERATURE CITED - AIZEN, — =. Chromosome reduction in Lilium canadense. Bor. GazeTTE 2 ——, Nuclear division in the pollen mother cells of Lilium canadenst Rederiet later Be 1905. : Kernsubstanzen wihrend der Syanpeis in ae angie von Tn Fonadense. sas Wiss. Bot. 42: 72-82. 1908] YAMANOUCHI—SPOROGENESIS IN NEPHRODIUM 25 7. ———,, II. Depuis le sporogonie jusqu’au spirtme définitif dans la micro-