INDEX OF SUBJECTS. 



581 



Discontinuity in the Variation of digits, 

 •407 

 in Meristic Variation of 



Radial Series, 423 

 partly dependent upon 

 Symmetry, 568 

 Discontinuous Variation, use of the term, 



15 

 Disease, analogy with Variation, 74 

 Ditomus tricuspidatux, double (?) an- 

 tenna, 550 

 Division of organs, a process of repro- 

 duction, 193 

 of teeth, 268; of mamma?, 193; 

 of digits, 349, 369; of ten- 

 tacles, 280 ; of radius of 

 Echinid, 446; median, 454 

 Dog, cervical rib, 122; hairless, 57; bull- 

 dog, 210, 221; digits, 401; nipples, 

 189 

 teeth, 209—222; incisors, 210; 

 canines, 211 ; premolars, 213, 

 215; molars, 220; deficiencies in 

 Esquimaux, 215; in Inca, 216 

 Dog-whelk, colour-variation, 48 

 Domestication, variability falsely ascrib- 

 ed to, 266, 401 

 Dunacia bidens, Variation in antennre, 



413 

 Dorcadion rufipes, extra legs, 512 

 Dorking Fowl, digital variations, 390 — 



395 

 Dorocidaris papillata, variation in pedi- 



cellaria?, 429 

 Double-foot, Artiodactyles, 378; Frog, 



540; Macacus, 340; Man, 337, 338 

 Double-hand, 325, 331 

 Double Monsters, 559 

 Double-thumb, 349 

 Dromceolus barnabita, extra antennae, 



523 

 Duck, no variation in number of digits 

 recorded, 401 ; cases of absence of 

 webs between toes, 401 

 Duplicity of single members of series not 

 distinct from other modes 

 of addition, 193, 407 

 of appendages, 406 ; in Arthro- 

 poda, 539; in Vertebrata, 

 539 

 axial, 559 

 Dutch pug, 57 



DyscJiirim globuloxus, extra legs, 512 

 Dytiscus marginalis, extra legs, 512 



Eagle, extra digits, 393 



Ears, repetitions of, known as cervical 

 auricles, 180 



Earthworms, variation of generative 

 organs, 159 ; of segmentation, 157 ; 

 asymmetrical arrangement of genera- 

 tive organs, 160, 161 ; table of arrange- 

 ment of ovaries, 162; duplicity of 

 head, 565, of tail, 565 



Earwig, variation of forceps, 40 ; of 

 antennary joints, 413 



Echinocomu, 4-rayed specimen, 441 ; 

 alleged case of 3 rays, 411 



Echinodermata, Meristic Variation in, 

 432; variations of pedicellaria-, 429; 

 duplicity, 



Echinoidea, Meristic Variation of, 411 ; 

 4-rayed specimens, 441; partial dis- 

 appearance of a ray, 413; partial 

 duplicity of a ray, 446; 6-rayed speci- 

 men, 445; pedicellariae, 429; variation 

 in number of genital pores, 446 ; sym- 

 metrical reduction of two rays, 4 13 



Echinus melo, partial reduction of an 

 ambulacrum, 443 



EcJtinus sphcera, partial reduction of an 

 interambulacrum, 445 



Ectrodactylism, Man, 355, 358 



Elater murinus, extra antennas, 522 ; 

 variabilis^ extra leg, 547 ; hirtus, 

 double (?) antenna, 551 



Elcdone, supernumerary hectocotylus. 

 473 



Eleodex pilosa, double (?) antenna, 551 



Elephas, tusks, 244; hoofs, 397 



Elytra, said to have been replaced by 

 legs in Prionus, 148 



Embryology, as a method of investigating 

 problems of Descent, 7 



Emperor moth, ocelli absent, 289, 301; 

 colour- variations of larva, 306 



Emu fowls, 55 



Enchytr&'idae, generative openings, 165 



Encrinus, variation in number of radial 

 joints, 421 ; 4-rayed calyces. 436 ; 

 radius bearing only one arm, 438 



Enema pan, extra legs, 512 



Entoniscians, alter segmentation of 

 some crabs but not of all, !'"> 



Enhydris, incisors, 211 



Epiglottis, division of, 451 



Epipodites, variation of in Hippolyte, 

 151 



Epistome (of Beetle), division of, 1">1 



Erebia bland inn, ocelli, 289 



Erinaceus, variation in hallux, 3'.i7 



Eriphia spinifrom, extra chela . 528 



Eros minutus, extra Legs, 487 



Enox Indus, bulldog-headed, 58 



Esquimaux Dog, absi ace of first pre- 

 molars, 214, 215, •-'•-'}_ 



Euchloe, pigments of, 72 



Eugeniacrinus, 4-rayed specimens, i 



Euprepia puipurea, extra palpi (alleged), 

 524 



Eurycephahu maxillosus^ extra legs, 1^7 



Euscnrpius, double tail, 565 



Eve of Palinurtu developed as antenna, 

 160 



Eye-colour of Man. 43 



Eye-spots, 288; Variation as a whole. 



291; outer /.one- first to appear, 291; 



analogy with chemical phenomena. 



