jaws,270;tube,285,290;colour,291,292;parasitic,297;tubes containing Polynoids,298;Palaeozoic,302Eunicites,301,302Euphrosyne,318;parapodium,265;chaetae,267Eupolia,113Eupolyzoa,461Eurycercus, shell of, inhabited by Rotifers,227n.Eurylepta,19Euryleptidae,19Eurythoe,318Eustrongylus gigas,142;E. tubifex,142Eusyllis, reproduction of,278Excretion, as cause of colour,291Excretory system, ofLeptoplana,13;of Polyclads,25;of Triclads,41;absent in Acoela,42;of Temnocephala,54;of Digenea,62;of Cestodes,86;of Nemertinea,108,108,120;of Nematodes,133;of Acanthocephala,177;of Rotifers,199,213;of Gastrotricha,234;of Kinorhyncha,237;of Polychaeta,253;of Polyzoa,472f.—see also NephridiumExogone,308;attachment of eggs,275;reproduction,278Eyes, ofLeptoplana,8,15;of Polyclads,26,27;development of,30;of larval Polystomatidae,59,60;of Nemertinea,102,106;of Nematodes,128;ofGordius,166;of Chaetognatha,188;of Rotifera,215;of Gastrotricha,234;of Kinorhyncha,238;of Polychaeta,255,272,314,337,339;of Oligochaeta,354;of Leeches,393,394,395;of Gephyrea,417;of Polyzoon larva,509Fabricia,339;eyes,272;otocyst,273Faecal groove, of Sabellids,337Fans, ofChaetopterus,295,324Faraday, on asexual reproduction of Planariae,6,40n.Farre, on Polyzoa,500,508Farrella,500,518,533Fasciola,67Fecampia, life-history,45Felt, ofAphrodite,268,312Fertilisation, of Nemertinea,117;of Nematodes,135;of Gordiidae,171;of Acanthocephala,179;of Chaetognatha,188;of Rotifers,217Filaria,147,163;F. attenuata,134;F. cystica,142;F. denticulata,125;F. immitis,148;F. labiata,163;F. laticaudata,125;F. loa,149;F. medinensis,147,157,163;F. sanguinis hominis,149,163;F. papillosa,163Filariidae,147Filigrana,340;fission in,281;tubes,290Fimbria tenuis,157Fischer, on branchiae in Gephyrea,416n.Fishes, Trematodes of,4,53,55,62,64,71,72;Cestodes of,77,84,85;Nemathelminthes of,142,143,149,163,173,182Fission, inBipalium,34;in Planariae,40;inTrichoplax,96;inSalinella,96;in Polychaeta,278f.,279,280,282,340;in Oligochaeta,374,375,377;in Phylactolaemata,496;in embryos,365,511Fissurella, as host,298Flabelligera,334Flame-cells, inLeptoplana,13;inThysanozoon,25;in Triclads,41;inTemnocephala,54;in Polystomatidae and Tristomatidae,56;inDistomum luteum,62;in Cestodes,86;in Nemertinea,108,109;in Rotifers,213;inUrnatella,491Fletcherodrilus,382Floscularia,200,203,205,220,221,226Flosculariaceae,202,211,213,220Flosculariidae,201,203,205,220n.,221,230Flukes,51Flustra,465,466,467,472,473,477,515,518,526;avicularia,482Flustrella,467,477,518,532;larva,513Flustrina,518Food, of Turbellaria,4;ofLeptoplana,10;of Polyclads,24;of Triclads,37;of Acoela,43f.;of Rhabdocoela,45;of Trematodes,4,52,62;ofTemnocephala,53;of Cestoda,5;of Nemertinea,115;of Nematodes,131;of Acanthocephala,177;of Chaetognatha,190;of Rotifera,207,212;of Gastrotricha,234;of Polychaeta,296;of Earthworms,359;of Leeches,393,406f.;of Gephyrea,422,443;of Polyzoa,467Foot, in Rotifers,200,201Foraminifera, as food of Polychaeta,296Forceps, ofEunice,270Forcipate,210,211Formula, for Nematoda,138Fornix,481,517,525Fossil, Polychaeta,301;Polyzoa,520;Nemertinea, absence of,119Fredericella,476,494,502-505,518,519;lophophore,495;statoblast,502,503Frenzel, on Trematoda,62;onSalinella,96Fresh-water, Turbellaria, compared with marine,46;Nemertinea,101,118;Polychaeta,284;Polyzoa,492Friend, on Oligochaeta,388n.Frogs, Trematodes of,55,58,62,71f.;Nematodes of,140,142,160,173Frontal organ, of Nemertinea,107Frontal palps, of Eunicidae,318f.Frontal ridge,260Frullania, inhabited by Rotifers,227Fulcrum, in Rotifers,210Funicular tissue,471Funiculus,469,471,472,499,501Furcularia,216,224,226Gamble, on Platyhelminthes,3f.;on Mesozoa,92f.Gammarus, Rotifers attached to,227Gapes, cause of,144Gardiner, on development of Acoela,44n.Gasterostomatidae,73Gasterostomum,73;G. fimbriatum, life-history,72;G. gracilescens,72Gastrocotyle,73Gastrodiscus,73Gastrothylax,73Gastrotricha,231f.Gegenbaur, on Nemertine development,99Gemellaria,518,526Gemmation,281;in Syllidae,278f.,279,280Geobia,37Geodesmus,34,42Geographical distribution, of Turbellaria,32f.;of Nemertinea,117;of Chaetognatha,191,534;of Gastrotricha,235;of Polychaeta,299f.;of Oligochaeta,369f.;of Leeches,405;of Gephyrea,426f.,432,441f.;ofPhoronis,460;of Polyzoa,492f.,504,519Geonemertes,101;description ofG. chalicophora,117Geoplana,33,38,42Geoplanidae,35,42Geoscolicidae,351,362,386Gephyrea,411f.;history,411;external characters,412,420f.,430f.,434f.,444;body-wall,414,436;digestive system,414,422,430,436,445;vascular system,415,421,436;respiratory system,416;body-cavity,416,437,445;nervous system,416,431,437,445;excretory system,417,423,431,437,445;reproductive system,418,431,437,445;development,419,439;food,422,443;commensalism,429;affinities,241n.,336,445f.,512;British,449Germarium, of Rotifers,216Germ-yolk-gland,47Giard, on Oligochaeta,368Gid, induced byCoenurus,82Gigantorhynchidae,183Gigantorhynchus gigas,174,177,184;G. echinodiscus,G. spira,G. taenioides,184Gills, of Polychaeta,252,265,268f.;ofArenicola,333;of Chlorhaemidae,334;ofCirratulus,326;ofEuphrosyne,265,318;of Eunicidae,318;ofNereis,246;of Sabelliformia,260,261;development of,275;ofSabella,286;colour of,294;ofSabellaria,263;of Serpulidae,261;ofSternaspis,336;of Sigalionina,313;of Terebellidae,329;of Oligochaeta,352,353;of Leeches,395;of Gephyrea,416Gizzard, in Rotifers,199,210;in Polychaeta,271,307;in Oligochaeta,358;in Polyzoa,477,480,532f.Glands, on parapodia,249;of Phyllodocids,314;oesophageal,271,272,358;tube-forming,287,304,327Gland shields,287,304,306;of Sabellids,337;of Terebellids,327Glandular papillae, ofPolygordius,244Glossiphonia(=Clepsine),393,396,399,404,407;anatomy,397,398,401;spermatophore,402Glossiphoniidae,406Glycera, cirrus,265;habitat,286;jaws,270;nephridium,254;parapodium,264;prostomium,259;tentacles,262;G. capitata, distribution,299;G. meckelii,320Glyceridae,258,320;gills,268;coelomic corpuscles,253Glyphidrilus,386Gnathobdellae,396f.,407Gnathobdellidae,407Gnathosyllis, colour of,293Gobio, parasites of,182,183Golfingia,426,428,430Goniada,320Goodrich, on Oligochaeta,378Gordiidae,123,164f.Gordiodrilus,383f.Gordius,164f.,164;G. tolosanus,165f.,170Gosse, on Rotifers,198,209n.,220Gossea,232,235Goujon, onTrichina,146Gourret, on Chaetognatha,187Graff, von, on Rhabdocoelida,44;onGeonemertes,101,117Graffilla,50;occurrence,45Grassi, on Cestoda,80n.,89;on Chaetognatha,190,193Grater, of Eunicidae,270Greef, on Echiuroidea,441,444Gregarines, in Polychaeta,299;in Gephyrea,444Gregory, on Polyzoa,519,520Grinder, of Eunicidae,270Grube, on Oligochaeta,347,352;
jaws,270;
tube,285,290;
colour,291,292;
parasitic,297;
tubes containing Polynoids,298;
Palaeozoic,302
Eunicites,301,302
Euphrosyne,318;
parapodium,265;
chaetae,267
Eupolia,113
Eupolyzoa,461
Eurycercus, shell of, inhabited by Rotifers,227n.
Eurylepta,19
Euryleptidae,19
Eurythoe,318
Eustrongylus gigas,142;
E. tubifex,142
Eusyllis, reproduction of,278
Excretion, as cause of colour,291
Excretory system, ofLeptoplana,13;
of Polyclads,25;
of Triclads,41;
absent in Acoela,42;
of Temnocephala,54;
of Digenea,62;
of Cestodes,86;
of Nemertinea,108,108,120;
of Nematodes,133;
of Acanthocephala,177;
of Rotifers,199,213;
of Gastrotricha,234;
of Kinorhyncha,237;
of Polychaeta,253;
of Polyzoa,472f.—see also Nephridium
Exogone,308;
attachment of eggs,275;
reproduction,278
Eyes, ofLeptoplana,8,15;
of Polyclads,26,27;
development of,30;
of larval Polystomatidae,59,60;
of Nemertinea,102,106;
of Nematodes,128;
ofGordius,166;
of Chaetognatha,188;
of Rotifera,215;
of Gastrotricha,234;
of Kinorhyncha,238;
of Polychaeta,255,272,314,337,339;
of Oligochaeta,354;
of Leeches,393,394,395;
of Gephyrea,417;
of Polyzoon larva,509
Fabricia,339;
eyes,272;
otocyst,273
Faecal groove, of Sabellids,337
Fans, ofChaetopterus,295,324
Faraday, on asexual reproduction of Planariae,6,40n.
Farre, on Polyzoa,500,508
Farrella,500,518,533
Fasciola,67
Fecampia, life-history,45
Felt, ofAphrodite,268,312
Fertilisation, of Nemertinea,117;
of Nematodes,135;
of Gordiidae,171;
of Acanthocephala,179;
of Chaetognatha,188;
of Rotifers,217
Filaria,147,163;
F. attenuata,134;
F. cystica,142;
F. denticulata,125;
F. immitis,148;
F. labiata,163;
F. laticaudata,125;
F. loa,149;
F. medinensis,147,157,163;
F. sanguinis hominis,149,163;
F. papillosa,163
Filariidae,147
Filigrana,340;
fission in,281;
tubes,290
Fimbria tenuis,157
Fischer, on branchiae in Gephyrea,416n.
Fishes, Trematodes of,4,53,55,62,64,71,72;
Cestodes of,77,84,85;
Nemathelminthes of,142,143,149,163,173,182
Fission, inBipalium,34;
in Planariae,40;
inTrichoplax,96;
inSalinella,96;
in Polychaeta,278f.,279,280,282,340;
in Oligochaeta,374,375,377;
in Phylactolaemata,496;
in embryos,365,511
Fissurella, as host,298
Flabelligera,334
Flame-cells, inLeptoplana,13;
inThysanozoon,25;
in Triclads,41;
inTemnocephala,54;
in Polystomatidae and Tristomatidae,56;
inDistomum luteum,62;
in Cestodes,86;
in Nemertinea,108,109;
in Rotifers,213;
inUrnatella,491
Fletcherodrilus,382
Floscularia,200,203,205,220,221,226
Flosculariaceae,202,211,213,220
Flosculariidae,201,203,205,220n.,221,230
Flukes,51
Flustra,465,466,467,472,473,477,515,518,526;
avicularia,482
Flustrella,467,477,518,532;
larva,513
Flustrina,518
Food, of Turbellaria,4;
ofLeptoplana,10;
of Polyclads,24;
of Triclads,37;
of Acoela,43f.;
of Rhabdocoela,45;
of Trematodes,4,52,62;
ofTemnocephala,53;
of Cestoda,5;
of Nemertinea,115;
of Nematodes,131;
of Acanthocephala,177;
of Chaetognatha,190;
of Rotifera,207,212;
of Gastrotricha,234;
of Polychaeta,296;
of Earthworms,359;
of Leeches,393,406f.;
of Gephyrea,422,443;
of Polyzoa,467
Foot, in Rotifers,200,201
Foraminifera, as food of Polychaeta,296
Forceps, ofEunice,270
Forcipate,210,211
Formula, for Nematoda,138
Fornix,481,517,525
Fossil, Polychaeta,301;
Polyzoa,520;
Nemertinea, absence of,119
Fredericella,476,494,502-505,518,519;
lophophore,495;
statoblast,502,503
Frenzel, on Trematoda,62;
onSalinella,96
Fresh-water, Turbellaria, compared with marine,46;
Nemertinea,101,118;
Polychaeta,284;
Polyzoa,492
Friend, on Oligochaeta,388n.
Frogs, Trematodes of,55,58,62,71f.;
Nematodes of,140,142,160,173
Frontal organ, of Nemertinea,107
Frontal palps, of Eunicidae,318f.
Frontal ridge,260
Frullania, inhabited by Rotifers,227
Fulcrum, in Rotifers,210
Funicular tissue,471
Funiculus,469,471,472,499,501
Furcularia,216,224,226
Gamble, on Platyhelminthes,3f.;
on Mesozoa,92f.
Gammarus, Rotifers attached to,227
Gapes, cause of,144
Gardiner, on development of Acoela,44n.
Gasterostomatidae,73
Gasterostomum,73;
G. fimbriatum, life-history,72;
G. gracilescens,72
Gastrocotyle,73
Gastrodiscus,73
Gastrothylax,73
Gastrotricha,231f.
Gegenbaur, on Nemertine development,99
Gemellaria,518,526
Gemmation,281;
in Syllidae,278f.,279,280
Geobia,37
Geodesmus,34,42
Geographical distribution, of Turbellaria,32f.;
of Nemertinea,117;
of Chaetognatha,191,534;
of Gastrotricha,235;
of Polychaeta,299f.;
of Oligochaeta,369f.;
of Leeches,405;
of Gephyrea,426f.,432,441f.;
ofPhoronis,460;
of Polyzoa,492f.,504,519
Geonemertes,101;
description ofG. chalicophora,117
Geoplana,33,38,42
Geoplanidae,35,42
Geoscolicidae,351,362,386
Gephyrea,411f.;
history,411;
external characters,412,420f.,430f.,434f.,444;
body-wall,414,436;
digestive system,414,422,430,436,445;
vascular system,415,421,436;
respiratory system,416;
body-cavity,416,437,445;
nervous system,416,431,437,445;
excretory system,417,423,431,437,445;
reproductive system,418,431,437,445;
development,419,439;
food,422,443;
commensalism,429;
affinities,241n.,336,445f.,512;
British,449
Germarium, of Rotifers,216
Germ-yolk-gland,47
Giard, on Oligochaeta,368
Gid, induced byCoenurus,82
Gigantorhynchidae,183
Gigantorhynchus gigas,174,177,184;
G. echinodiscus,G. spira,G. taenioides,184
Gills, of Polychaeta,252,265,268f.;
ofArenicola,333;
of Chlorhaemidae,334;
ofCirratulus,326;
ofEuphrosyne,265,318;
of Eunicidae,318;
ofNereis,246;
of Sabelliformia,260,261;
development of,275;
ofSabella,286;
colour of,294;
ofSabellaria,263;
of Serpulidae,261;
ofSternaspis,336;
of Sigalionina,313;
of Terebellidae,329;
of Oligochaeta,352,353;
of Leeches,395;
of Gephyrea,416
Gizzard, in Rotifers,199,210;
in Polychaeta,271,307;
in Oligochaeta,358;
in Polyzoa,477,480,532f.
Glands, on parapodia,249;
of Phyllodocids,314;
oesophageal,271,272,358;
tube-forming,287,304,327
Gland shields,287,304,306;
of Sabellids,337;
of Terebellids,327
Glandular papillae, ofPolygordius,244
Glossiphonia(=Clepsine),393,396,399,404,407;
anatomy,397,398,401;
spermatophore,402
Glossiphoniidae,406
Glycera, cirrus,265;
habitat,286;
jaws,270;
nephridium,254;
parapodium,264;
prostomium,259;
tentacles,262;
G. capitata, distribution,299;
G. meckelii,320
Glyceridae,258,320;
gills,268;
coelomic corpuscles,253
Glyphidrilus,386
Gnathobdellae,396f.,407
Gnathobdellidae,407
Gnathosyllis, colour of,293
Gobio, parasites of,182,183
Golfingia,426,428,430
Goniada,320
Goodrich, on Oligochaeta,378
Gordiidae,123,164f.
Gordiodrilus,383f.
Gordius,164f.,164;
G. tolosanus,165f.,170
Gosse, on Rotifers,198,209n.,220
Gossea,232,235
Goujon, onTrichina,146
Gourret, on Chaetognatha,187
Graff, von, on Rhabdocoelida,44;
onGeonemertes,101,117
Graffilla,50;
occurrence,45
Grassi, on Cestoda,80n.,89;
on Chaetognatha,190,193
Grater, of Eunicidae,270
Greef, on Echiuroidea,441,444
Gregarines, in Polychaeta,299;
in Gephyrea,444
Gregory, on Polyzoa,519,520
Grinder, of Eunicidae,270
Grube, on Oligochaeta,347,352;