INDEX 



681 



Mantle-groove, formation of, in Paludina, 

 314 



Mantle-layer, definition of, 63 



Mauubriuin of medusa of Podocoryne, 61 ; 

 of Tubularia, 58 



Mastax, formation of, ill Callidina russeola, 

 424 



Maturation, divisions of germ-cells, 3 ; of 

 egg, in Crepidula, 7, 8 ; of spermatozoon, 

 in Lepidosiren, 4-6 



Maxillipedes, development of, in larva of A ch- 

 theres ambloplitis, 207 ; in Astacus, 186 ; 

 in Mysis larva of Craugonidae, 215 ; in 

 Cyclops, 197 



Mayer's fixative, 35 



Median dorsal arm of ciliated band of larva 

 of Asterias, 464 



Median retractor muscle of larva of Dreis- 

 sensia, formation of, 341 



Median ventral arm of ciliated band of larva 

 of Asterias, 464 



Medullary folds, formation of, in embryo of 

 Cynthia partita, 619 



Medullary plate, formation of, in embryo of 

 Amphioxus lanceolatus, 591 



Medusa-buds (see Gonophore) of Siphono- 

 phora, 66; of Tubularia, development of, 57 



Medusae, free, development of eggs of, 59- 

 61 



Meilusome theory of Haeckel, 66 



Mt-;_ r ;ilopa larva of Brachyura, 216 



Melicertidea, 418 



Mellita testudinata, 504, 522 



Jlelolontha, 287 ; abdominal appendages of, 

 266 



Membranipora, development of, 387-394 



Membranipora pilosa, 387 



Meridional canals, formation of, in Bertie, 94 



Meroblastic segmentation, definition of, 26 ; 

 in eggs of Arthropoda, 178 ; in eggs of 

 Cephalopoda, 178, 353 ; in eggs of Pera- 

 carida, 193 ; in eggs of Pyrosoma, 632 ; 



. in eggs of Scorpion, 240 ; in eggs of Sepia, 

 353 



Mesectodenn in Annelida, Mollusca, and 

 Gephyrea, 401 ; formation of, in Lepas, 

 195 ; in Mollusca, 323 ; in Patella, 309 ; 

 in Phascolosoma, 376 ; in Planocera, 111 ; 

 in Polygordius, 135 



Mesencliyme, definition of, 120 ; formation 

 of, in embryo of Antedon rosacea, 545 ; 

 in larva of Asterias, 461 ; in larva of 

 Balanoglossus clavigerus, 573 ; iir larva of 

 Cerebratulns lacteus, 120 ; in larva of Cu- 

 cumaria planci, 542 ; in larva of Cynthia 

 partita, 614 ; of Grant ia, 39 ; in larva 

 of Holothuria ti'bulosa, 541 ; in larva 

 of Ophiura brevispina, 501 ; in larva of 

 Pedicellina echinata, 401 ; in embryo of 

 Pyrosoma, 635 ; in larva of Synfipta 

 digitata, 531 



Mesendoderm, formation of, in Crepidula, 

 323 ; in Dreissensia, 335 ; in Fiona, 323 ; 

 in Phy'sa, 323 ; in Sepia, 356 



Mesenteric stomata of Urticina crassicornis, 

 80 



Meseuterial filaments of Urticina crassicornis, 

 81 



Mesentery of Urticina crassicornis, 79 



Mesoderm, formation of, iu Agelena, 224 ; 

 mAlcyonidiuM albidum, 388 ; inAmphi- 

 O.CHS lanceolatus, 592 ; in Astacus, 180 ; 

 in Beroe, 93 ; iu Blatta, 261 ; in Crepidula, 

 322 ; in Donacia, 248 ; in Dreissensia, 

 335 ; in Euphausia, 192 ; in Fiona, 322 ; 

 in Lepas, 195 ; in Limulus, 236 ; in 

 Neplwlis, 161 ; in Oligochaeta, 156 ; in 

 Pallene, 243 ; in Paludina, 310 ; in 

 Patella, 295 ; in Pedicellina, 399 ; iu 

 Pedipalpi, 241 ; in Phascolosoma, 375 ; 

 in Physa, 322 ; iu Planocera, 108 ; in 

 Polygordius, 143 ; in Polyphemus, 194 ; 

 in Salpa, 636 ; in Scorpion, 240 



Mesodermal bands, formation of, in Agelena, 

 225 ; in Dentalium, 329 ; in Lepas, 195 ; 

 in Lepisma, 265 ; in Oligochaeta, 156 ; in 

 Paludina, 310 ; in Patella, 299 ; in 

 Pedicellina, echinata, 401 ; in Peripatus 

 capensis, 171 ; in Polygordius, 138 ; in 

 Polygordius appendiculatus, 144 ; in 

 Scolopendra, 283 



Mesogloea of Urticina crassicornis, 79 



Mesomeres in egg of Echinus esculentus, 506 



Mesonemertini, 118 



Mesotrochal larva, definition of, 153 



Metamorphosis of Copepodid larva of A chtheres 

 ambloplitis, 207, 208 ; of larva of Amphi- 

 oxus lanceolatus, 603, 604 ; of larva of 

 simple Ascidiau, 622 ; of larva of As- 

 terias, 467-472 ; of the larva of Asterina 

 gibbosa, 474-479 ; of Zoaea larva of 

 Brachyura, 215 ; of larva of Ciona intesti- 

 nalis, 622-628 ; of pupa of Cirripedia, 

 202 ; of Mysis larva of Crangonidae, 215 ; 

 of larva of Cyclops, 198, 199 ; of larva of 

 Dreissensia, 343 ; of larva of Echinus 

 esculentus, 512-518 ; of Insects, 266-280 ; 

 of larva of Jfembranipora, 394 ; of larva 

 of Ophiothrix fragilis, 492-498 ; of larva 

 of Ostracoda, 203 ; of larva of Pedicellina 

 echinata, 402, 403 ; of larva of Phascolo- 

 soma, 377, 378 ; of larva of Phoronis 

 (Actinotrocha), 383, 384 ; of larva of 

 Polygordius append iculatus, 149-151 ; of 

 larva of Synapta digitata, 536-541 ; of 

 larva of Terebratidina septentri&nalis, 412, 

 413 ; of New England Tornaria larva, 

 577-579 ; of Nassau Tornaria larva, 580, 

 581 ; of the larva of Yungia (Pilidium), 

 112-115 



Metauauplius larva of Cyclops, 198 ; of 

 Stomatopoda, 216 



Metanauplius stage in development of 

 Achtheres ambloptitis, 206 



Metanemertini, 118 



Metanephridia, formation of, in Polygordius, 

 147 



Metasyndesis, definition of. 12 



