n6 



SEX AND HEREDITY 



Correlation, coefficient of, 105 : 

 the measure of degree of depen- 

 dence of one variable upon 

 another. 



Crossing, 38. 



Cutleria, 18 ; 19. 



Datura, seed of, 49. 

 Death, not a necessary sequel to 

 life, 60, 88 : in higher animals, 



63- 

 Depression, 60. 



Dominant, a character of one 

 parent, which develops in the 

 body of a hybrid to the ex- 

 clusion of the corresponding 

 character of the other parent, 97. 



Echidna, 77. 



Ectocarpus secundus, male and 

 female gametes of, 17. 



Ectocarpus siliculosus, isogametes 

 of, 15, 16, 17. 



Egg, 4 : of birds, 72, 74. 



Embryo, internal in land-plants, 

 50 : of bird, 76 : of mammal, 

 poisoning or infection, 80. 



Embryo-sac, a large cell within 

 which is the ovum in flowering 

 plants, 44. 



Eugenics, the science of the im- 

 provement of the race, especially 

 through the agency of selection, 

 112. 



Euglena, 9 : life history of, 10, 32. 



Factor, (hereditary) : the hypo- 

 thetical physical entity in the 

 germ-plasm which is concerned 

 with the production of any 

 particular feature of the body ; 



^ 95, 99- 



Female gamete, or macrogamete, 

 or ovum : the female sexual 

 cell, which is usually non- 

 motile, and is larger than the 

 male gamete which fuses with 

 it': 4- 



Fern, sexual propagation of, 24 : 

 attraction of spermatozoids by 

 ovum, 34. 



Fertilization, the fusion of the 

 male gamete or spermatozoid 

 with the female gamete or 

 ovum : the term is equivalent 

 of syngamy : in a Fern, 26 : 

 in a flowering plant, 29, 37, 41, 

 46 : in Cyclops, 82, 83. 



Fish-like characters in embryos/ 

 67. 



Fission, in Euglena, 10 : in Copro- 

 monas, 55 : in body of higher 

 animals, 62. 



Flower, a dense group of organs 

 borne on the end of a stalk in 

 flowering plants, in connection 

 with which the gametes are 

 produced, 27. 



Foot, the suctorial organ of the 

 embryo in Ferns, 35, 36. 



Frog-spawn, 68. 



Fitcus, gametes of ; 3 : fertiliza- 

 tion of, 20 : attraction of 

 spermatozoids by ovum of, 33. 



Funiculus, stalk of ovule or seed, 

 42, 49. 



Fusion of sexual cells, or syngamy, 



3- 



Gametangium, a cell which pro- 

 duces gametes : of Ectocarpus, 

 17 : of Cutleria, 19. 



Gamete, or sexual cell : a cell 

 which is capable of fusing with 

 another cell in a sexual act, 3 : 

 of Fucus, 5 : of man, 5 : of 

 Ulothrix, 12 : of Ectocarpus, 16, 

 17 : of Cutleria, 19 : of Orchis, 

 29 : of Copromonas, 57 : of 

 Plasmodium, 59 : of Stylo- 

 rhynchus, 58. 



Germ-cell, a gamete, or cell which 

 will give rise to a gamete, 81. 



Germ-plasm, living substance 

 which is able to give rise to 

 complete new individuals. 88. 



