Mammals (L. mamma, breast), warm-blooded, hairy animals which suckle their young.
Maturation (L. maturus, ripe), the final stages in the development of the sex-cells characterized by two divisions in one of which the number of chromosomes is reduced by one-half.
Mendelian, Mendelism, referring to Mendel, the founder of a theory of heredity. See p. 67.
Metazoa (Gr. meta, over; zoon, animal), all animals higher than the protozoa.
Mitosis (Gr. mitos, thread), indirect nuclear division, characterized by the appearance of a fibrous spindle and a definite number of chromosomes. The latter split to form daughter chromosomes which diverge to the poles of the spindle to form parts of the new nuclei.
Mongolian, a type of feeble-minded individual, see p. 248.
Monohybrid (Gr. monos, single; L. hybrida, mongrel), the offspring of parents, differing in one character.
Moron (Gr. moros, foolish), defined, p. 244.
Mutations (L. mutare, to change), abrupt, inheritable germinal variations. Frequently though not necessarily they are changes of considerable extent.
Neural (Gr. neuron, nerve), pertaining to the nervous system.
Neuron (Gr. neuron, nerve), a nerve-unit consisting of a nerve-cell with branching processes called dendrites and an axon or axis cylinder process which gives rise to a nerve fiber.
Neuropathic (Gr. neuron, nerve; pathos, suffering), relating to disease of the nervous system.
Nucleolus (L. dim. of nucleus), a well-defined body found within the nucleus of a cell.
Nucleus (L. nux, a nut), the central organ of a cell.
Nulliplex (L. nullus, not any; plico, fold), the condition in which no determiners of a given character exist in a particular individual.
Oöcyte (Gr. ōon, egg; kytos, cell), the ovarian egg in one stage of development.
Oögenesis (Gr. ōon, egg; genesis, origin), the development of ova from primitive sex-cells.
Oögonium (Gr. ōon, egg; gonos, generation), a primordial egg-cell.
Ovary (L. ovum, egg), the organ in which the egg-cells multiply and are nourished.
Ovum (L. ovum, an egg), the female sex cell.
Parthenogenesis (Gr. parthenos, virgin; genesis, origin), development of an egg which has not united with a male gamete.
Phenotype (Gr. phaino, show; typto, strike), the existing type of individual irrespective of hereditary possibilities which may reside in it undeveloped.
Phototropism (Gr. phos, light; tropē, turning), defined, p. 198.
Placenta (L. placenta, a flat cake), the organ by which the fetus of the higher mammals is attached to the uterine wall of the mother for purposes of nourishment, respiration and excretion. In it the maternal and fetal blood, although not intermingling, are brought into such close proximity that an interchange of dissolved substances is possible.
Polar Bodies, the minute cells which are separated from the egg in its maturation divisions.
Primate (L. primus, first), the highest order of animals, including monkeys, apes and man.
Pronucleus, the nucleus of the mature ovum or sperm-cell.
Protoplasm (Gr. protos, first; plasma, form), the essential living substance.
Protozoa (Gr. protos, first; zoon, animal), single-celled animals or animals composed of cells not separable into different tissues.
Psychical (Gr. psyche, the soul), pertaining to the mind.
Recessive Character (L. recessus, a going back), a character from one parent which remains undeveloped in offspring when associated with the corresponding dominant character from the other parent.
Reduction Division, a division of the maturing germ-cells in which the dual or somatic (diploid) number of chromosomes is reduced to the single (haploid) number.
Reflex Action (L. re, back; flectere, bend), an automatic response of the nervous and motor mechanism of the body.
Restrictive (or negative) Eugenics, a system of improving the human race by preventing reproduction of the unfit.
Reversion (L. re, back; verto, turn), the reappearance of ancestral traits which have for some generations been in abeyance.
Rheotropism (Gr. rheo, to flow; tropē, turning), defined, p. 198.
Salpingectomy (Gr. salpinx, trumpet; ectomē, cutting out), removal of part or all of a Fallopian tube (oviduct).
Segregation (L. se, aside; grex, flock), separation.
Sex Chromosome, a special chromosome which is supposed to be concerned in the determination of sex.
Sex-Linked Characters, defined, p. 60.
Simian (L. simia, ape), ape-like.
Simplex (L. sim, same; plico, fold), the condition in which a character is represented by a determiner from only one of the two parents.
Soma (Gr. soma, body), the body considered apart from the germ-cells.
Spermatid (Gr. sperma, seed), a cell resulting from the last division of the germ-cell in spermatogenesis. It transforms into the spermatozoon.
Spermatocytes (Gr. sperma, seed; kytos, cell), cells concerned in the maturation divisions of the male germ-cells.
Spermatogenesis (Gr. sperma, seed; genesis, origin), the development of spermatozoa from primitive sex-cells.
Spermatogonium (Gr. sperma, seed; gonos, generation), a primordial sperm-cell.
Spermatozoon (Gr. sperma, seed; zoon, animal), the functional male sex-cell.
Spindle, a fibrous organ formed in indirect cell-division.
Spireme (L. spira, coil), a characteristic stage preliminary to indirect cell-division in which the chromatin material of the nucleus appears in the form of a skein of filaments.
Stereotropism (Gr. stereos, solid; tropē, turning), defined, p. 198.
Sterilization (L. sterilis, barren), deprivation of reproductive power. For methods, see p. 322.
Synapse (Gr. syn, together; hapto, unite), the coming in contact of the processes of one nerve cell with the processes or body of another.
Synapsis (Gr. syn, together; hapto, unite), union of the chromosomes in pairs preliminary to the reduction division.
Telegony (Gr. telegonos, born far away), the supposed influence of an earlier sire on offspring born later of the same mother to a different sire.
Thermotropism (Gr. thero, heat; tropē, turning), defined, p. 198.
Thigmotropism (Gr. thigmo, touch; tropē, turning), defined, p. 198.
Toxin (Gr. toxicon, poison), poisonous compounds of animal, vegetable, or bacterial origin.
Tropism (Gr. tropē, turning), the automatic directing of an organism toward or away from a source of stimulus.
Unit-Character, a character which behaves as an indivisible unit in heredity.
Vasectomy (L. vas, vessel; ektomē, cutting out), removal of a portion of the vas deferens (duct for conveying spermatozoa).
Vestigeal (L. vestigium, footstep), representing organs which existed once in a more developed condition.
Volvox (L. volvo, roll), a small fresh-water organism occurring in spherical colonies.
Wasserman Reaction, a test for syphilis, see p. 188.
X-Element, same as sex-chromosome.
Zygote (Gr. zygon, yolk), the product of the union of two gametes.
REFERENCES FOR FURTHER READING AND STUDY
Bateson, W., 1909. Mendel’s Principles of Heredity. Cambridge, The University Press. The best technical account of Mendelism. It contains also a translation of the original papers of Mendel.
Castle, William E., 1911. Heredity. New York, D. Appleton and Company.
Castle, William E.; Coulter, John M.; Davenport, Charles B.; East, Edward M.; Tower, William L., 1912. Heredity and Eugenics. Chicago, The University of Chicago Press.
Conklin, Edwin Grant, 1915. Heredity and Environment in the Development of Men. Princeton, Princeton University Press.
Davenport, Charles B., 1911. Heredity in Relation to Eugenics. New York, Henry Holt and Company.
Doncaster, L., 1911. Heredity in the Light of Recent Research. Cambridge, The University Press.
Doncaster, L., 1915. The Determination of Sex. Cambridge, The University Press.
Ellis, Havelock, 1912. The Task of Social Hygiene. New York, Houghton Mifflin Company.
Galton, Francis, 1869. Hereditary Genius: an Inquiry Into Its Laws and Consequences. London, Macmillan and Company.
Galton, Francis, 1889. Natural Inheritance. New York, The Macmillan Company.
Galton, Francis, 1895. English Men of Science; Their Nature and Nurture. New York, D. Appleton and Company.
Galton, Francis, and Schuster, Edgar, 1906. Noteworthy Families (Modern Science). London, J. Murray.
Goddard, Henry Herbert, 1912. The Kallikak Family; a Study in the Heredity of Feeble-mindedness. New York, The Macmillan Company.
Goddard, Henry Herbert, 1914. Feeble-mindedness; Its Causes and Consequences. New York, The Macmillan Company.
Healy, William, 1915. The Individual Delinquent. Boston, Little, Brown and Company.
Kellicott, William E., 1911. The Social Direction of Human Evolution; an Outline of the Science of Eugenics. New York, D. Appleton and Company.
Morgan, Thomas Hunt, 1913. Heredity and Sex. New York, Columbia University Press.
Punnett, R. C., 1911. Mendelism. New York, The Macmillan Company. The best popular account of Mendelism.
Saleeby, Caleb William, 1909. Parenthood and Race Culture; an Outline of Eugenics. London, Cassell and Company.
Schuster, Edgar, 1912. Eugenics. London, Collins Clear-Type Press.
Thomson, J. Arthur, 1908. Heredity. London, John Murray.
Walter, Herbert Eugene, 1913. Genetics. New York, The Macmillan Company.
Whetham, W. C. D. and C. D., 1909. The Family and the Nation. London, Longmans, Green and Company.
Woods, Frederick Adams, 1906. Mental and Moral Heredity in Royalty. New York, Henry Holt and Company.
Various Authors, 1914. Eugenics; Twelve University Lectures. New York, Dodd, Mead and Company.
Journals:
The Journal of Heredity. The organ of the American Genetic Association, Washington, D. C.
The Eugenics Review. Issued at the University of London.
Memoirs and Bulletins published by the Eugenics Record Office, Cold Spring Harbor, Long Island, N. Y.
Every one interested in eugenics should be acquainted with the work of this office. In its own words its functions are:
1. To serve eugenical interests in the capacity of repository and clearing house.
2. To build up an analytical index of the traits of American families.
3. To train field workers to gather data of eugenical import.
4. To maintain a field force actually engaged in gathering such data.
5. To cooperate with other institutions and with persons concerned with eugenical study.
6. To investigate the manner of inheritance of specific human traits.
7. To advise concerning the eugenical fitness of proposed marriages.
8. To publish results of researches.
To such persons as will undertake to fill them out it furnishes free in duplicate (one copy to be retained by the applicant) the following blank schedules: 1. Record of Family Traits. 2. Index to Germ-plasm—A Parallel Family Record for Prospective Marriage Mates. 3. Musical Talent. 4. Mathematical Talent. 5. Tuberculosis. 6. Special Trait Chart. 7. Harelip and Cleft-palate.
Publications of the Volta Bureau of Washington, D. C., an institution given over entirely to data regarding deaf mutes.
Studies in National Deterioration. The University of London.
Memoirs and Lectures, from the Biometric Laboratory, University of London.
Treasury of Human Inheritance, a series of studies being issued from the Eugenics Laboratory, University College, London.
INDEX