This book is intended for use in connection with college and university courses in the biological sciences. It is not a new edition of the author's "Introduction to Cytology," which was designed to serve both as a reference work, of which plant cytology was in need, and as a general textbook. This is a textbook only. Although it deals again with various principal topics of the older work and uses some of its illustrations along with many new ones, the present text is much briefer, simpler in treatment, and, it is hoped, better adapted to the needs of students whose curiosity concerning cytology has been newly aroused in elementary courses in animal and plant science. The title of the older book, in fact, might well have been reserved for this one. Where subjects not essential to an introductory treatise are included, it is not with the thought that they should be mastered now, but rather to indicate further fields of inquiry open to students of cytology.
No attempt has been made to maintain the connection between statement and source characteristic of the "Introduction to Cytology." Each chapter has, however, been provided with a short list of books and recent papers for the use of those who wish to begin an examination of the literature, but to avoid distraction the text has been left unencumbered by specific references to them. Anyone who prepares a book of this kind knows well that he is presenting mainly the work of authors whose names do not appear on the title page, and he only trusts that he does this with accuracy and fairness.
The selection, arrangement, and treatment of the various topics have been determined by experience in cytology courses having a genetical and phylogenetical bearing. In the interest of simplicity, emphasis has been placed upon "typical" cytological phenomena. Care has been taken, however, to suggest the great diversity in cytological constitution and behavior exhibited by plants and animals and to indicate the many uncertainties in a field where growth is rapid and opinions are subject to change with new evidence. It is unfortunate that the terminology could not be further simplified without impairing the usefulness of the book for those preparing to consult the literature. As every experienced teacher of natural science is aware, the student's actual knowledge of the subject is gained primarily in the field and laboratory. It is there, by thoughtful observation and discussion, that his comprehension is . . .