INDEX 



281 



Pea, culinary — 

 stature of, 12 (Fig. 6) 

 fasciated variety of, 21 (Fig. 8) 

 texture of pods of, 24 (Fig. 9) 

 colour of pods of, 26 (Fig. 10) 

 colour of seed-coats of, with 



simple dominance of grey, 27 



(Figs. 11 and 12) 

 colour of seed-coats of, giving 



reversionary purple spots in 



first cross, 114 (Fig. 27) 

 colour of seed-coats of, maple and 



purple spot, 110 (Fig. 26) 

 colour of flowers of, 118 (Plate 



IV.) 

 colour of cotyledons of, 53 



(Plate I.) 

 shape of cotyledons, 66 (Fig. 21) 

 colour and shape of cotyledons, 



93 (Plate III.) 

 1:2:1 ratio in. Oh. II. and 



Frontispiece 

 3:9:4 ratio in, 114 (Fig. 27) 

 9:3:3:1 ratio in, 93 (Plate III.), 



110 (Fig. 26) 

 Presence and Absence — 

 hypothesis, 126 

 its application to cotyledon shape, 



130 

 its application to cotyledon colour, 



131 

 evidence relating to, 137 

 its application to theory of sex, 



257 

 Purity, gametic, 217 

 Purple spotted pea, 110 



Ratio — 

 1:2:1 

 in peas, 16 

 in fowls, 34 



Ratio — 



1:2:1 (continued) 

 in successive hybrid genera- 

 tions, 70-71 

 in mice, 76 

 9:3:3:1 



in peas ; cotyledon characters, 



97 

 seed-coat characters, 112, 115 

 3:9:4 

 in peas ; flower-colour, 119 

 similarity of 3 : 9 : 4 to 1 : 2 : 1, 

 121 

 Recessive characters, the number 

 of generations it takes to com- 

 bine them, 104 

 Reid, Dr. Archdall, 267 

 Reversion, 74 



Roan colour in cattle, 80, 178 

 "Rust" in wheat, 138 



Sacculina, effect of, on sex of crabs, 



260 

 Seed, the nature of a, 52 

 Segregation, the essential feature 



of Mendelian inheritance, 38, 80 

 Selectionist, point at issue between 



the, and mutationist, 4-5 

 Sex— 



Dr. Archdall Reid's theory of 



the inheritance of, 26 ' 

 Dr. Dawson's, 258 

 the Mendelian, 251 

 Sex-limited inheritance, 248 

 Simplex eye, 41 

 Smith, ]\Ir. Geoffrey, his theory of 



sex, 251 

 Soma, 239 

 Specimens illustrating Mendel's 



results, method of mounting, 



150 



