[5] For this drawing, and also those of Figures 1 and 4, I am indebted to Professor A. C. Haddon; the larval form A is the young of Clavelina, found at Torquay. [6] Petromyzon (_petra_, stone; _myzo_, to suck). [7] Myxine. [8] Cyclostomata (_cyclos_, circle; _stoma_, mouth). [9] Called _conodonts_, and found in Lower Silurian rocks earlier than any bones of true fish. [10] Carcharias glaucus. [11] Homocercal. [12] Heterocercal. [13] Acipenser sturio. [14] Isinglass is made from the covering of this air-bladder. [15] Lepidosteus. [16] Polypterus. [17] Amia. [18] Lepidosiren. [19] Protopterus. [20] Ceratodus. [21] These fish, coiled round, may be seen in the British Museum. [22] Ichthyodorulites. [23] Dipterus. [24] Dinichthys. [25] See Frontispiece. 1, Chauliodus; 2, 9, 10, 11, Harpodon or Bombay Duck; 3, Plagiodus; 4, Chiasmodus, with a Scopelus in its stomach; 6, Beryx; 8, Scopelus. [26] In drawing up this sketch of the deep sea I am almost entirely indebted to Dr. Günther’s masterly sketch of the deep-sea fish in his excellent work. [27] Echeneis remora. [28] Naucrates. [29] In this description I am not alluding simply to the mackerel _family_ Scombridæ, but to that much larger group _Cotto-Scombriformes_, to which so many ocean fish belong, and even the sword-fish is allied. [30] Thynnus pelamys. [31] Thynnus thynnus. [32] Coryphæna. [33] Lampris luna. [34] Exocœtus. [35] Coryphæna. [36] Dactylopterus. [37] Hippocampus. [38] Xiphias. [39] At least 10,000 for each mother. [40] Mullus. [41] Trigla. [42] Gobidæ. [43] Cyclopterus. [44] Trachinidæ. [45] Lophius piscatorius. [46] Lophius. [47] Uranoscopus. [48] Solea vulgaris. [49] Hippocampus. [50] Gasterosteus. [51] Cottus. [52] Siluridæ. [53] More properly eel-fares (_fare_, Saxon, to travel; ex., way-_faring_ man). [54] Anabas. [55] Not “waddling;” it is the toad, not the frog, that waddles. [56] Lissotriton punctatus. [57] _Amphi_, all around; _bios_, life. [58] Proteus anguineus. [59] Salamandra atra. [60] See Picture-heading, p. 70. [61] Labyrinthodonts (_Laburinthos_, spiral; _odontas_, teeth). [62] Rhacophorus Rheinhardii. [63] Alytes obstetricus. [64] Pipa Americana. [65] Protorosaurus or Thuringian lizard. [66] Ichthyosaurus. [67] Plesiosaurus. [68] Mosasaurus and Clidastes. [69] Pterodactyls. [70] Iguanodon in Europe, Hadrosaurus in America. [71] Megalosaurus in Europe, Dryptosaurus in America. [72] Testudo Græca. [73] Testudo talenlata. [74] The parts of the joints which flatten out in the tortoise are seen at _sp_ in the lizard and snake, pp. 103, 111. [75] Testudinea. [76] Terrapins. [77] Emyx and Trionys. [78] Chelydra serpentina. [79] Chelonia midas. [80] Chelonia imbricata. [81] Zootoca vivipara. [82] Ophisaurus ventralis. [83] Anguis fragilis. [84] Natrix torquata. [85] Naja. [86] Crotalus. [87] Naja tripudians. [88] _Ichthyopsida_--_ichthys_, fish; _opsis_, appearance.