INDEX. 



683 



Medullary plate, 501 

 Medullary sheath, 96 

 Medusae, 144, 230, 234 

 Megalops, 434 

 Megalonyx, 636 

 Megalosphaeres, 198 

 Megatherium, 636 

 Megascolex, 316 

 Megastoma, 202 

 Meissner's corpuscles, 126 

 Melanoplus, 481 

 Meleagrina, 367 

 Meleagris, 614 

 Melitta, 346 

 Meloidse, 484 

 Melolontha, 484 

 Melonites, 345 

 Melophagus, 493 

 Melopsittacus, 616 

 Membracidse, 490 

 Membrane bones, 515 

 Membranipora, 324 

 Membranellse, 209 

 Membranous cranium, 519 

 "Menopoma, 587 

 Mentum, 464 

 Menuridse, 619 

 Mephitis, 647 

 Meridional furrows, 151 

 Mermithidoe, 304 

 Meroblastic cleavage, 153 

 Meroblastic eggs, 152, 154 

 Meryhippus, 643 

 Mesectoderm, 222 

 Mesencephalon, 533 

 Mesenchyme, 157 

 Mesenterial filaments, 252 

 Mesenteries, 109, 545 

 Mesenteron, 105 

 Mesethmoid bone, 522 

 Mesites, 613 

 Mesoblast, 157 

 Mesobronchus, 609 

 Mesoderm, 104, 157 

 Mesoglcea, 230 

 Mesohippus, 643 

 Mesonemertini, 291 

 Mesonephros, 550 



Mesonephric duct, 550 

 Mesopterygium, 529 

 Mesorchium, 546 

 Mesotroche, 309 

 Mesosternum, 462 

 Mesothelium, 158 

 Mesothorax, 462 

 Mesozoic era, 180 

 Mesovarium, 546 

 Metabolism, 172 

 Metacarpal bones, 529 

 Metagenesis, 144 

 Metameres, 137, 305 

 Metamerism, 137 

 Metamorphosis, 161 

 Metamorphosis of insects, 473 

 Metanemertini, 291 

 Metanephric duct, 550 

 Metanephros, 550 

 Metapodium, 369 

 Metapterygium, 529 

 Metastoma, 430 

 Metatarsal bones, 529 

 Metathorax, 462 

 Metazoa, 221 

 Metencephalon, 533 

 Methona, 48 

 Metridium, 259 

 Miastor, 492 

 Mice, 639 

 Micraesthete, 357 

 Microcentrum, 481 

 Microchiroptera, 638 

 Microconodon, 632 

 Microcotyle, 274 

 Microdrilaa, 315 

 Microgametes, 185 

 Microlepidoptera, 494 

 Microlestes, 632 

 Micronucleus, 206 

 Micropterus, 577 

 Micropylar apparatus, 148 

 Microsphaeres, 198 

 Microstomidae, 271 

 Microthelyphonida, 448 

 Micrura, 292 

 Midas, 651 

 Mid brain, 533 



