ONTIIOl'HAGUS. 



INDEX. 



66s 



femora of the male, and on the 

 head and thorax of the female, 

 297. 



Dnthophagus, 295. 



■ rangifer, sexual differences of, 



296 ; variation in the horns of the 

 male, 297. 



Ophidia, sexual differences of, 351. 



Op/iidium, 347. 



O^iossum, wide range of, in America, 

 169. 



Optic nerve, atrophy of the, cansed 

 oy destruction of the eye, 32. 



Orang-Outan, 561 ; Bischoff on the 



' agreement of the brain of the, 

 with that of man, 6 ; adult age 

 of the, 8 ; ears of the, 14 ; ver- 

 miform appendage of, 21 ; hands 

 of the, 60 ; absence of mastoid pro- 

 cesses in the, 53 ; platforms built 

 by the, 66 ; alarmed at the sight of 

 a turtle, 72 ; using a sticls as a 

 lever, 81 ; using missiles, 81 ; using 

 the leaves of the Fandanus as a 

 night coveiing, 82 ; direction of 

 the hair on the arms of the, 151 ; 

 its aberrant characters, 154; sup- 

 posed evolution of the, 177 ; voice 

 of the, 527 ; monogamous habits 

 of the, 590 ; male, beard of the, 

 531. 



Oranges, treatment of, by monkeys, 

 50. 



Orange-tip butterfly, 308, 312, 313. 



Orcliestia Darwinii, dimorphism of 

 males of, 268. 



■ Tucuratinga, limbs of, 267, 271. 



Ordeal, trial by, 96. 



Oreas canna, colours of, 535. 



Dcrbianus, colours of, 535, 543. 



Organs, prehensile, 209 ; utilised for 



new purposes, 571. 



Oi'sjanic scale, von Baer's definition of 

 progi'ess in, 164. 



Oi-ioles, nidification of, 453. 



Oriolus, spicies of, breeding in im- 

 mature plumage, 484. 



— melanooephalus, coloration of the 

 sexes in, 460. 



Ornaments, prevalence of similar, 

 179 ; of male birds, 367 ; fondness 

 of savages for, 574. 



Ornamental characters, equal trans- 

 mission of, to both sexes, in mam- 

 Bale, 541 ; of monkeys, 549. 



Omithoptera crcesus, 250. 



Ornithorhynohus, 156 ; reptilian ten- 

 dency of, 159; spur of the male, 

 502. 



Orocetes erythrogastra, young of, 487. 



OiTony, Grotto of, 22. 



Orsodacna atra, difference of colour io 

 the sexes of, 294, 



Orthoptera, 282; metamoi-phosis of, 

 237 ; stridulating apparatus of, 

 283, 288; colours of, 289; rudi- 

 mentary stridulating organs in 

 female, 288; stridulation of the, 

 and Homoptera, discussed, 288. 



Ortygamis gulans, pugnacity of the 

 male, 363. 



Oryctes, stridulation of, 303 ; sexual 

 diffprences in the stridulani organs 

 of, 305. 



Oryx leucoryx^ use of the horns of, 

 509, 518. 



Osphranter rufus, sexual difference in 

 the colour of, 533. 



Ostrich, African, sexes and incuba- 

 tion of the, 478. 



Ostriches, stripes of young, 464. 



Otarla jubata, mane of the male, 

 521. 



nigresccns, difference in th« 



coloration of the sexes of, 534. 



Otis bengalensiSj love-antics of the 

 male, 380, 



tarda^ throat-pouch of the male, 



373; polygamous, 219. 



Ouzel, ring-, colours and nidification 

 of the, 455, 



, water-, colours and nidifica- 

 tion of the, 455. 



Ovibos moschatits, horns of, 505. 



Ovipositor of insects, 208. 



Ovis cydoceroSj mode of fighting of, 

 508, 513, 



Ovule of man, 9, 



Owen, Prof., on the Corpora Wolf- 

 fiana, 11 ; on the great toe in man, 

 11 ; on the nictitating membrane 

 and semilunar fold, 17 ; on the 

 development of the posterior mo- 

 lars in different races of man, 20 ; 

 on the length of the coecum in the 

 Koala, 20; on the coccygeal ver- 

 tebrsB, 23 ; on rudimentary struc- 

 tures belonging to the reproductive 

 system, 24 ; on abnormal condi- 

 tions of the human uterus, 38 



