ANALYTICAL INDEX 



435 



Interest as a stimulus to inquiry, 

 xliv-xlvi. 



Internal Causes, theory of, as sug- 

 gested explanation of mimicry, 224, 

 225, 272 ; obviously inapplicable to 

 mimicry between remote species, 229; 

 also inapplicable to protective resem- 

 blances, 227, 228; objections to, as 

 explanation of mimicry, 227-9, 233, 

 236-9, 241, 245, 247, 249, 250, 257, 

 260-2, 266-8, 273, 275, 276, 278-82. 



Internal Sci. Ser., 161 n. I. 



INTERSPECIFIC STERILITY AS 

 TEST OF SPECIES, II. 77-80: see 

 also 59. 



INTERSPECIFIC STERILITY CAUSED 

 BY ASYNGAMY, II. 80-4 : see also 

 65, 91 ; see also sterility. 



INTIMIDATING ATTITUDES, X. 



3 2 4, 325- 



INTIMIDATING OR WARNING 

 SOUNDS, X. 324. 



Introduction, Kirby and Spence, 

 utility of mimicry suggested in (1817), 

 221, 222. 



INTRODUCTION : MUTATION, 

 MENDELISM, AND NATURAL 

 SELECTION, xiii-xlviii. 



INTRODUCTION TO DISCUSSION 

 'WHAT is A SPECIES?' II. 63-5. 



INVESTIGATION, THE MOTIVE 

 FORCE OF, Introd., xlvii, xlviii. 



iopterus, Promachus, mimicry of 

 Hymenoptera by, 257 n. i. 



iraivada, see splendens, Isamia, 

 376. 



Ireland, dread of snake-like cater- 

 pillar in, 367 n. 2. 



Iridescence, cryptic effect of, 322. 



Irrawaddy R., 291 n. i. 



Isamia splendens and irawada, 

 376. 



ISLANDS, ANCESTRAL NON- 

 MIMETIC FORMS PRESERVED ON, 

 X. 373-6- 



Islands, oceanic, wingless insects 

 in, 1 8. 



Isolation and species production, 

 76 ; leading to ' mechanical selec- 

 tion', 85. 



Ithomid) a central type of Ithomiine 

 pattern, 234. 



Ithomiinae (see also classification 

 of examples of mimicry, 383-4, 386-8): 

 collected by Burchell in Brazil, 53 

 n. I ; Heliconinae and, as examples of 

 Mullerian mimicry, 232 ; always tend 



to be mimicked, 233, 273 ; number of 

 colours in Neotropical Papilioninae 

 compared with those of, 234, 277 ; as 

 models paralleled by Diabrotica, 236 ; 

 pigments of, different from those of 

 Pierine mimics, 262, 263 ; trans- 

 parent-winged species of and mimics, 

 264-6 ; colours of principal combina- 

 tions grouped round in various 

 localities, 272, 273, 322, 331-3, 350, 

 35*> 356; darkening of, in the 

 Guianas, 272, 273, 331-3 ; dominance 

 of, in British Guiana, 332 ; uniformity 

 throughout many species of, 234, 277 ; 

 long confused with Heliconinae, 278 ; 

 not extremely conspicuous, 322 ; 

 absence of ' eye-spots ' in, 326 ; 

 equivalent to the Danaoid Helico- 

 nidae of Bates, save for inclusion in 

 latter of Danaine Ituna and Lycorea, 

 327 ; distinguished by flight from 

 mimicking Heliconinae, 331, 331 n. i ; 

 resemblance of Heliconinae to, re- 

 markable in mimicry, 343 ; mimicked 

 by an Erycinid which is itself the 

 model of diurnal moth, 346 ; Helico- 

 nine close mimics of, generally at 

 once distinguishable, 350. 



Ituna and Thyridia, a re- 

 markable case of Mimicry in 

 Butterflies, Fritz Miiller, 222: see 

 also 212, 226, 278, 327. 



Ituna (Danainae), mimicry of 

 Ithomiinae by, 265 ; method of 

 attaining transparency in, 265, 266 ; 

 included in Ithomiinae by Bates, 

 327- 



J 



Jacob, experiments of, on flocks of 

 Laban, 186. 



jacobaeae, Euchelia, larva of a 

 Mullerian mimic of a wasp, 230 ; 

 cryptic and aposematic defence of 

 larva of, aposematic of imago, 318, 



3I9- 



Jacoby, M., on mimicry in Coleo- 

 ptera, 236, 237. 



Jagellon, intermarriage with, the 

 cause of a hereditary peculiarity of 

 lip in Royal House of Austria, 180. 



Japan, Z. chrysippus reported 

 from, 88. 



Jardin des Plantes, Paris, O. 

 lamarckiana originally described 

 from, xxi. 



Jen. Zeit., 317. 



f 2 



