PROFESSOR AT THE UNIVERSITY OF LOUVAIN,
CORRESPONDENT OF THE INSTITUTE OF FRANCE.

WITH EIGHTY-THREE ILLUSTRATIONS.

NEW YORK:

D. APPLETON AND COMPANY,

549 & 551 BROADWAY.
1876.

CONTENTS.
page
INTRODUCTION.
Adaptation of Food to Animals—Animal Manufacturers—Brigands—Messmates—Mutualists—Theory of Spontaneous Generation[xiii]

CHAPTER I.
ANIMAL MESSMATES.
Definition—Free Messmates—Fixed Messmates[1]

CHAPTER II.
FREE MESSMATES.
Found in all Classes—Fierasfers in Holothuridæ—Pilot Fish—Remora—Crustacean Messmates—Poisoning by Mussels—Pearl Mussel and small Crab—Dromiæ—Turtle Crabs—Macrourous Decapods—Hermit Crabs—Friendship of Pagurus and Anemone—Isopods—Messmates on Whales—Molluscan Messmates—Lerneans—Distomes—Messmates of the Echinodermata—Of Sponges—Infusorial Messmates[4]

CHAPTER III.
FIXED MESSMATES.
Cirrhipedes—Importance of Embryology—Recurrent Development—Messmates, characteristic of the various Species of Whales—Cirrhipedes on Sharks—Crustaceans, Messmates on other Crustaceans—Cirrhipedes on Molluscs—Bryozoa—Fossil Messmates—Messmates on Sponges—Spicules of Hyalonema—Ophiodendrum[53]

CHAPTER IV.
MUTUALISTS.
Definition—Ricinidæ—Trichodectes of Dog harbouring Larva of Tænia—Arguli—Caliguli—Ancei—Pranizæ—Cyami—Nematode Mutualists—Strange form of Histriobdellæ—Egyptian Distome in Man[68]

CHAPTER V.
PARASITES.
Distinction between Parasites and Carnivora—Parasites found on all Classes of Animals—Males dependent on Females—Parasites on Man—Abundant Parasites in Stork—All the Organs nourish Parasites—Different size of Male and Female—Lerneans—Diplozoa—Migration of Parasites—Corresponding Changes of Form—Parasites restricted to certain Regions—Former Theory of Spontaneous Generation[85]

CHAPTER VI.
PARASITES FREE DURING THEIR WHOLE LIFE.
Leeches—Vampires—Cylicobdellæ—Branchellions—Gnats—Blackflies—Mosquitoes—Gnats in high Latitudes—Tsetse—Ox-flies—Pteropti—Nycteribiæ—Bugs—Lice—Fleas—Itch Insect—Acari on Beetles and Bees—Cheyletus eruditus[107]

CHAPTER VII.
PARASITES FREE WHILE YOUNG.
Isopod Parasites—Chigoe—Ticks—Pigeon-mite—Bopyridæ—Ichthoxenus—Peltogasters—Tracheliastes—Penellæ—Lerneans—Guinea-worm—Leptodera of Snail—Nematodes in Bones—Lichnophoræ—Gregarinæ[138]

CHAPTER VIII.
PARASITES THAT ARE FREE WHEN OLD.
Utility of Ichneumons—Scoliæ of Tan-beetles—Scolyti of Seychelles Cocoa-nut Trees—Elms at Brussels destroyed by Scolyti—Polynema in Eggs of Dragon-fly—Sphex—Platygaster— Horse-fly—Livingstone—Animals in Paraguay destroyed by Hippobosci—Dipterous Parasites on Sheep and Stag—Gordius—Shower of Worms—Eels in Ears of Corn [162]

CHAPTER IX.
PARASITES THAT MIGRATE AND UNDERGOMETAMORPHOSES.
Nostosites—Xenosites—Hosts serving as a Crèche, a Vehicle, or a Lying-in Hospital—Lamarck on Spontaneous Generation—Trematodes—Monostomes—Sporocysts and Cercariæ—Passage from one Host to another—Distomes—Flukes—Hemistomes—Amphistomes—Tæniæ of the Dog and Wolf—Hydatids—Tænia solium in Man—Cysticercus of Pig—Cysticercus of Rabbit and Hare passing into Dog—Cœnurus of Sheep—Bothriocephalus—Linguatula in Negro—Strongyli—Trichinæ—Panic in Germany—Vibriones in Corn—Echinorrhynchus—Dicyema[183]

CHAPTER X.
PARASITES DURING THEIR WHOLE LIFE.
Strepsitera—Stylops—Rhipiptera—Tristomidæ—Epibdella—Diplozoon, two Individuals—Polystomum of Frog—Gyrodactyles—Cochineal Insect—Aphides—Phylloxera of Vine—An Acaris, its Mortal Enemy—Ant-Cows—Bonnet’s Theory of Germs—The Reduvius personatus, a valuable enemy to the Bed-bug[255]

LIST OF ILLUSTRATIONS.
fig.page
[1.]Ophiodendrum abietinum on Sertularia abietina66
[2.]Ricinus of the Pygarg72
[3.]Caligulus elegans, female: ditto, natural size73
[4.]Different forms of the Bite of a Leech110
[5.]Sucker and jaws110
[6.]Anatomy of Leech110
[7.]Antenna of Gnat115
[8.]Gnat, male and female118
[9], [10.]Lucilia hominivora120
[11.]Ox-fly121
[12.]Antenna of Ox-fly121
[13.]Blue-fly121
[14.]Flesh-fly122
[15.]House-fly122
[16.]Bed-bug124
[17.]Louse125
[18.]Louse—Suckers126
[19.]Ditto—Claw126
[20.]Flea (Pulex irritans)128
[21.]Itch-mite131
[22.]Ditto, female—back view131
[23.]Ditto, male—back view132
[24.]Geographical water-mite136
[25.]Book-mite137
[26.]Chigoe, male141
[27.]Ditto, head141
[28.]Ditto, female141
[29.]Phryxus Rathkei145
[30.]Tracheliastes of Cyprinidæ149
[31.]Lernea branchialis attached to Morrhua luscus151
[32.]Young Guinea-worm, showing Mouth, Tail, and section of Body153
[33.]Gregarinæ of Nemertes160
[34.]Sac with Psorospermiæ from Sepia officinalis160
[35.]Stylorhynchus Melophagus oligacanthus from Dragon-fly161
[36.]Horse-fly, showing also Anterior and Posterior Extremity172
[37.]Macaco Worm175
[38.]Melophagus of the Sheep177
[39.]Lipoptena of Stag177
[40.]Gordius aquaticus178
[41.]Monostomum verrucosum—Sporocyst with Cercariæ191
[42.]Liver fluke198
[43.]Monostomum mutabile202
[44.]Ditto, ciliated Embryo and young Cercariæ202
[45.]Cercaria of Amphistoma sub-clavatum203
[46.]Sporocyst of Amphistoma sub-clavatum203
[47.]Ditto, from Frog205
[48.]Polystomum integerrimum205
[49.]Cysticercus206
[50.]Vesicular Worm211
[51.]Tape-worm (Tænia solium), showing Scolex and Proglottides214
[52.]Ditto, Rostellum and Suckers214
[53.]Tænia medio-canellata219
[54.]Cœnurus of Sheep, and Hydatid223
[55.]Scolex of Tænia echinococcus226
[56.]Tænia echinococcus from the Pig226
[57.]Ditto, from the Dog227
[58.]Bothriocephalus latus227
[59.]Scolex of ditto227
[60.]Egg of ditto227
[61.]Tænia variabilis from Snipe230
[62.]Ditto, more highly magnified230
[63.]Tetrarhynchus appendiculatus from the Plaice230
[64.]Hook of Linguatula232
[65.]Linguatula, showing Hooks232
[66.]Strongylus gigas, female239
[67.]Ascaris lumbricoides; also Head, Tail, and Body240
[68.]Trichocephalus from Man241
[69.]Oxyuris vermicularis, natural size and magnified241
[70.]Trichina, free243
[71.]Trichina encysted in Muscle243
[72.]Echinorhynchus proteus252
[73.]Sac with Psorospermiæ from Sepia officinalis252
[74.]Gregarinæ from Nemertes Gesseriensis253
[75.]Stylorhynchus oligacanthus253
[76.]Dicyema Krohnii from Sepia officinalis254
[77.]Stylops256
[78.]Ditto, with Embryos257
[79.]Larva of Black Stylops257
[80.]Cochineal Insects, male263
[81.]Ditto, female264
[82.]Aphis264
[83.]Rose Aphis, male and female265