XIV CONTEXTS. 



PAGE 



CHAPTER III. VERTEBRA AND RIBS . ... 102 



CHAPTER IV. SPINAL NERVES . . .129 



CHAPTER V. VARIATION IN ARTHROPODA 146 



CHAPTER VI. CH.'ETOPODA, HIRUDIXEA AXD CESTODA . . 156 



CHAPTER VII. BRANCHIAL OPENINGS OF CHORDATA AND STRUC- 

 TURES IN CONNEXION WITH THEM . . . 171 

 1. Ascidians. 2. Cyclostomi. 3. Cervical Fistulas and Super- 

 numerary Auricles in Mammals 



CHAPTER VIII. MAMM.-E . . . 181 



CHAPTER IX. TEETH 195 



Preliminary. Primates. Canidae. Felidit. Vivc-rrida?. Muste- 

 liila?. Pinnipedia. Marsupialia. Selacbii. Radulas of Biiccimiin. 



CHAPTER X. TEETH RECAPITULATION .... 265 



CHAPTER XI. MISCELLANEOUS EXAMPLES 274 



Scales. Kidneys; Eenal Arteries; Ureters. Tentacles and Eyes 

 of Mollusca. Eyes of Insects. Wings of Insects. Horns of 

 Sheep, Goats and Deer. Perforations of shell of Haliotis. 



CHAPTER XII. COLOUR-MARKINGS 288 



Ocellar Markings. Simultaneity of Colour- Variation in Parts 

 repeated in Linear Series (Larvae of Lepidoptera : Chitonidje) 



CHAPTER XIII. MINOR SYMMETRIES: DIGITS . . 311 



CAT. Pp. 313324. 



MAN AND APES. Pp. 324360. 



Increase in number of digits, p. 324. 



Cases of Polydactylism associated with chaniie of Symmetry. A. 



Digits in one Successive Series, p. 326. B. Digits in two 



homologous groups forming '"Double-hands," p. 381. Complex 



cases, p. 338. 

 Polydttctyliam not associated with chanije of Symmetry, p. 344. (1) 



A. Single extra digit external to minimus, p. 345. (1) B. 



Single extra digit in other positions, p. 349. (2) Duplication of 



single digits, p. 349. (3) Combinations of the foregoing, p. 352. 



(4) Irregular examples, p. 353. 

 Keduction in number of phalanges, p. 355. Syndactylism, p. 356. 



Absence of digits and representation of two digits by one, p. 358. 



HORSE, pp. 360 373. Extra digits on separate metacarpal or meta- 

 tarsal, p. 361. More than one digit borne by metacarpal III., 

 p. 369. Intermediate cases, p. 371. 



ARTIODACTYLA, pp. 373 390. Polydactylism in Pecora, p. 373. Poly- 

 dactylism in Pig, p. 381. Syndactylism in Artindactyla, p. 383. 



BIRDS, pp. 390395. 



Possibly Continuous numerical Variation in digits : miscellaneous 

 examples, pp. 395 398 (Ch<ilfi<l<:<. Cixtudo. liismi. Krhnifi'im. 

 F.li'plm.-i.) Inheritance of Digital Variation. Association of 

 Digital Variation with other forms of Abnormality. 



