INDEX 



Acer negundo, reversion in, 338 



Actiniae, regeneration in, 127 



Adler, on galls, 219 



Adventitious buds, Sachs's view of, 

 211; formation by means of ac- 

 cessory idioplasm, 212, 218 



Alternation of generations, in its 

 relation to the idioplasm, 173; 

 hereditary variability of individual 

 generations, 174; in Daphnidse, 

 175; in Aphis, 178; in Medusse, 

 1 79 ; caused by two kinds of 

 germ-plasm, 182, 457 



Amphimixis, or the intermingling 

 of individuals, 20, 24; its relation 

 to reproduction, 232; resulting in 

 complications in the composition 

 of the germ-plasm, 235 ; the cause 

 of all reversion, 337; the means 

 of producing variation, 413; its 

 relation to bud-variations, 439; 

 the cause of an increase or de- 

 crease in the development of a 

 character, 464 



Ancestral germ-plasms — not anal- 

 ogous to Spencer's • physiological 

 units,' II 



Antirrhinum majus, Darwin's ex- 

 periments with the peloric form 



of, 331 

 Aphis, alternation of generations, 



178 



Ascaris megalocephala, the chromo- 

 somes of, 86; diagram, fig. 18, 

 page 233 



Ascidians, regeneration, 139; eggs 

 contrasted with those of frogs, 

 141; gemmation, 160; compari- 

 son of gemmation with embry- 

 ogeny, 162 



Auerbach, on nuclear division, 23 



Balfour, phylogeny of gemmation, 

 169 



Balsamine, transmission of varia- 

 tions of, 445 



Baumann, chemical constitution of 

 protoplasm, 40 



Bees, polymorphism in, 376 



Begonia, adventitious buds, 2X1 



Beneden, Ed. van, observations on 

 fertilisation of egg in Ascaris, 23; 

 function of the centrosomes, 25 ; 

 view concerning idants, 244 



Biophors, or bearers of vitality, the 

 smallest vital units, 40; a group of 

 molecules on which the phenom- 

 ena of life depend, 40; resem- 

 blance to Spencer's 'physiological 

 units,'40; difference between them 

 and Nageli's ' micellfe.' 4I ; de 

 Vries's ' pangenes,' and Wiesner's 

 ' plasonies,' 42; bearers of cell- 

 qualities, 42; number of kinds 

 unlimited, 44; all protoplasm 

 constituted by, 45 ; their size and 

 number, 85; combined anew in 

 the formation of galls, 221, 448 



Beyerinck on galls, 219; gall of 

 A'ematus, 222 



Blending, of parental characters not 

 a fundamental phenomenon of 

 heredity, 8; of paternal and ma- 

 ternal i(lio]:>lasm in ontogeny, 253 ; 

 of parental characters in the off- 

 spring, 261, 266, 297 



Blood-corpuscles controlled by de- 

 terminants, 57 



Blumenbach's ' nisus formativus,' 

 103, 104 



Bonellia viridis, its dimorphism, 364 



Bonnet, on the regeneration of eye 

 of Triton, 125; on worms, 131 



469 



