IXDEX 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 triciispidatus, 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 

 Dvnacia bidens, Variation in antenna?, 



413 

 Dorcadion rufipes, extra legs, 512 

 Dorking Fowl, digital variations, 390 — 



395 

 Dorocldaris 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 

 Dronueolus barnabita, extra antenna?, 



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 



Dyschirius globulc-sus, 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 



Echinoconus, 4-rayed specimen, 441 ; 

 alleged case of 3 rays, 441 



Echinodermata, Meristic Variation in, 

 432; variations of pedicellaria?, 429; 

 duplicity, 



Echinoidea, Meristic Variation of, 441 ; 

 4-rayed specimens, 441; partial dis- 

 appearance of a ray, 443 ; partial 

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

 men, 445; pedicellaria?, 429; variation 

 in number of genital pores, 446 ; sym- 

 metrical reduction of two rays, 443 



Echinus melo, partial reduction of an 

 ambulacrum, 443 



Echinus splicera, partial reduction of an 

 interambulacrum, 445 



Ectrodactylism, Man, 355, 358 



Elater murinus, extra antenna?, 522 ; 

 variabilis, extra leg, 547 ; hirtus, 

 double (?) antenna, 551 



Eledone, supernumerary hectocotylus. 

 473 



Eleodes 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, 3U6 



Emu fowls, 55 



Enchytra?ida?, 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, 95 



Enhydris, incisors, 211 



Epiglottis, division of, 451 



Epipodites, variation of in Hippolyte, 

 151 



Epistome (of Beetle), division of, 454 



Erebia blandina, ocelli, 289 



Ennaceus, variation in hallux, 397 



Eriphia spinifrons, extra chelse, 528 



Eros minutus, extra legs, 4*7 



Eso.v lucius, bulldog-headed, 58 



Esquimaux Dog, absence of first pre- 

 molars, 214, 215, 221 



Euchloe, pigments of, 72 



Eugeniacrinus, 4-rayed specimens, 436 



Euprepia purpurea, extra palpi (alleged), 

 524 



Eurycephalus maxillosus, extra legs, 487 



Euscorpius, double tail, 565 



Eye of Palinurus developed as antenna, 

 150 



Eye-colour of Man, 43 



Eye-spots, 288 ; Variation as a whole, 

 291 ; outer zones first to appear, 291 ; 

 analogy with chemical phenomena, 



