Melolontha, 457, 458, 495 



Melophagus, 512 



Membranellae, 17, 104 



Membranipora, 608, 609, 613 



Menopon pallidum, 483 ; 484 



Mentum, 427 



Mermis, 256; 249; mgrescens, 256 



Merodon, 511 



Merogametes, 31, 89 



Meropodite, 336 



Merozoites, see Schizozoites 



Mesenchyme, 129; 130 and n., 131, 

 134, 142, 197; of Acoelomata, 197; 

 of Ctenophora, 195; of Echino- 

 dermata, 631; of Hirudinea, 298; 

 of Nemertea, 236; of Platyhel- 

 minthes, 205; of trochosphere, 281 



Mesenteric caeca, of Aphrodite, 268 ; 

 of Arachnida*, 315, 517, 534, 539; 

 of Crustacea*, 344, 358, 367, 379, 

 391, 392, 393, 397, 412; of 

 Echinodermata*, 626, 636, 646, 

 656; of Insecta, 434. See also 

 Digestive gland, Liver 



Mesenteric filaments, 182, 187 



Mesenteries, of Actinozoa, 182, 187, 

 188, 190; of Holothuroidea, 650; 

 of Polychaeta, 285 ; of Scyphozoa, 

 174, 178 



Mesenteron (Mid gut), 130; of Crus- 

 tacea*, 344, 358, 367, 412; of 

 Hirudinea, 297 ; of Insecta, 433 ; of 

 Nematoda, 248 



Mesoblast, see Mesoderm 



Mesoblastic somites, see Mesoderm 

 segments 



Mesocerebrum, see Deutocerebrum 



Mesoderm, 129; i, 131, 134, 142, 

 143 ; in the trochosphere, 281, 285 ; 

 of Arachnida, 520; of Arthropoda, 

 316; of Chordata, 661, 675; of 

 Insecta, 452. See also Mesen- 

 chyme, Mesoderm segments, Me- 

 sothelium 



Mesoderm segments (Mesoblastic 

 somites), 316; 135; of Annelids, 

 285; of Arachnida, 516, 520; of 

 Arthropoda, 314, 316; of Chaeto- 

 poda, 261, 285 ; of Chordata, 661 ; 

 of Onychophora, 319 



Mesogloea, see Structureless lamella 



Mesosoma, 309, 517, 522, 524 



Mesostoma, 211; 204 ; ehrenbergi, 2x4 ; 

 quadr angular e, 214 



INDEX 709 



Mesothelium, 129; 131, I33, 135. 



142, 143. See also Mesoderm 



segments 

 Metabasipodite, see Preischiopodite 

 Metabola, see Pterygota 

 Metaboly, 17, 52 



Metacerebrum, see Tritocerebrum 

 Metacestode stage, 228 

 Metachronal rhythm, 17; 195 

 Metameric segmentation, 285 

 Metamorphosis, see Life history 

 Aletanauplius larva, 353, 373 

 Metanemertini, 237; 233 

 Metapneustic, 508; 509, 511 

 Metasicula, 170 

 Metasoma, 309, 517, 521, 524 

 Metasome, 372 

 Metasternite, 522 

 Metastoma, of Crustacea, 339: of 



Eurypterida, 525 ; of Trilobita, 323 

 Metatroch, 284 



Metazoa, 128 ; i, 7, 8, 27, 35, 45, 124 

 Metazoaea larva, 389 

 Metepipodites, 336, 337. See also 



Branchia 

 Metridium, 193 

 Miastor, 446, 509 

 Microchromosomes, 26 

 Microfilaria diurna, 255 ; nocturna, 



255 

 Microgametes, see Male gametes 

 Microhydra, 165; 162 

 Micromeres, 281 

 Micronephridia, 290 

 Micronuclei, 26; 33, 34, 35, 107, no, 



115 

 Micropterygidae, 488, 490 

 Micropteryx, 488, 490 

 Microspheric form, 76 

 Microsporidia, 102 

 Microstoma lineare, 214; 213 

 Mid gut, see Mesenteron 

 Mid-gut caeca, see Mesenteric caeca 

 Milk glands of tsetse fly, 446 

 Millepora, 165, 165 

 Mitoses of Protozoa, 24 

 Molar process, 387 

 Mollusca, 543 ; i, 2; Types of, 544 

 Molpadida, 652 



Mo?7as, 63; 16, 42, 46; vulgaris, 62 

 Monaxonida, 127 and n. 

 Monocyclical rotifers, 241 

 Monocystis, 97; 12, 31, 37, 38, 96, 97; 



lumbrici, 97; magna, 97 



