Effort, 385, 386 
Embryonic, 391, 397, 398 
Emperoceras, 566, 568, 
570, 575, 578, 614 
Beecheri, 575, 579, 
613 
Enclimatoceras, 563 
Ulrichi, 563 
Endoceras, 363, 368, 400, 
403, 404, 582 
Endoceratidee, 412, 415 
Endolobus, 536, 601 
avonensis, 536, 607 
spectabilis, 536 
Endosiphonoidea, 404 
Entergogenesis, 386, 387, 
39° 
Epacme, 393, 397 
Epembryonic, 392, 410 
Ephebic, 381, 391, 397, 
398, 409, 410, 417, 445, 
473 
Ephebology, 392 
Ephippioceras, 602 
Epinepionic, 392 
Epineanic, 392 
Ergogeny, 386 
Estonioceras, 446, 
520, 536, 607 
ariense, 522, 536 
biangulatum, 521, 523 
decheni, 522 
heros, 522 
imperfectum, 
521, 524, 584 
lamellosum, 522, 526 
perforatum, 521, 523, 
524 
Eudoceratidze, 535 
Eurystomites, 433, 434; 
441, 456, 592, 601 
Kelloggi, 372, 442, 
597, 607 
gibbosum, 443, 456 
rotundus, 443 
undatum, 445 
: Virginiana, 444 
Eutrephoceras, 548, 555, 
558, 560, 587, 605 
Dekayi, 556, 560, 587 
457, 
520, 
643 
Eutrephoceras faxoense, 
558 
imperialis, 559, 605 
Evolution, law of, 367, 
371 
Exiteloceras, 568 
pariense, 577 
angulatum, 577 
Cheyennense, 577 
Jennyi, 577 
uncum, 577 
Falcilituites, 433, 446, 457, 
520, 522 
Decheni, 457 
Muellaueri, 458 
Fissurella, 380, 588 
Foord, 404 
Funnels, 404 
Genesiology, 383, 390, 412 
Gephuroceras, 414 
Geratology, 392 
Gerontic, 381, 391, 397, 
398, 410, 417, 419, 472 
Glossoceras, 513 
Glyphioceras atratus, 609 
crenistria, 609 
Gomphoceras, 585 
Goniatites, 368 
Goniatitinze, 355, 361, 369, 
371, 410, 411, 412, 413, 
414, 416, 584, 609, 610, 
616 
Growth, law of, 381 
Gyroceras, 432 
Elrodi, 454 
inelegans, 535 
minusculum, 493 
nudum, 492 
ohioense, 497 
proximum, 495 
Stebos, 497 
Habitat, action of, 375 
Haeckel, 390, 392, 393, 
397 
Hall, 361 
Halloceras, 518 
Hamites, 566, 613, 614 
Fremonti, 577 
Hamulina, 566 
Helicancylus, 565, 570 
zequicostatus, 565 
Helicoceras, 566, 613 
navarroensis, 572 
pariense, 577 
simplicostatum, 569 
Stevensoni, 568 
umbilicatum, 569 
Hercoceratidz, 491 
Hercoceras, 492, 599 
irregularis, 493, 599 
mirum, 492, 493, 599 
nudum, 492 
secundum, 493 
transum, 492 
Hercoglossa, 563 
Hering, 384 
Heteroceras, 574 
angulatum, 577 
Cheyennense, 577 
Conradi, 569 
helecinum, 573 
nebrascense, 574 
Newtoni, 574 
Holm, 463, 468, 471, 506, 
509, 570 ; 
Holmiceras, 512 
przecurrens, 509 
Hymenoptera, 401 
Hyponome, 353 
Impressed zone, 407, 408 
Jackson, 350, 365, 392, 
396 
Kinetogenesis, 386 
Koninckioceratidze, 545 
Kophinoceras, 518 
Lamarck, 358, 387 
Lepidoptera, 401 
Lindigia, 569 
helicoceroides, 569 
Lispoceras sulciferum, 544 
Litoceras, 474, 485 
biangulatum, 476 
