The following list, which contains only the principal genera and groups of coast fishes, will give an idea of the affinity of the tropical Atlantic and Indo-Pacific:—[28]
| Trop.-Atl. | Indo-Pac. | |
| Scylliidæ | — | 13 |
| Pristis | 3 | 4 |
| Rhinobatidæ | 4 | 8 |
| Torpedinidæ | 1 | 8 |
| Trygonidæ | 14 | 24 |
| Etelis | 1 | 1 |
| Aprion | — | 1 |
| Apsilus | 1 | — |
| Centropristis | 15 | — |
| Anthias | 4 | 5 |
| Serranus | 30 | 85 |
| Plectropoma | 11 | 5 |
| Grammistes | — | 2 |
| Rhypticus | 3 | — |
| Diploprion | — | 1 |
| Myriodon | — | 1 |
| Mesoprion | 15 | 50 |
| Priacanthus | 4 | 12 |
| Apogon and Chilodipterus | 2 | 75 |
| Pristipoma | 12 | 14 |
| Hæmulon | 15 | — |
| Diagramma | — | 30 |
| Gerres | 12 | 16 |
| Scolopsis | — | 20 |
| Dentex and Symphorus | — | 7 |
| Synagris and Pentapus | — | 24 |
| Cæsio | — | 12 |
| Mullidæ | 5 | 22 |
| Sargus | 7 | 2 |
| Lethrinus | 1 | 18 |
| Chrysophrys | 1 | 7 |
| Pimelepterus | 1 | 5 |
| Squamipinnes | 13 | 110 |
| Toxotes | — | 2 |
| Cirrhites | — | 20 |
| Scorpænidæ | 2 | 65 |
| Myripristis | 3 | 15 |
| Holocentrum | 6 | 25 |
| Platycephalus | — | 25 |
| Prionotus | 1 | — |
| Trigla | — | 4 |
| Peristethus | 2 | 6 |
| Uranoscopina | 2 | 8 |
| Champsodon | — | 1 |
| Percis | — | 10 |
| Sillago | — | 5 |
| Latilus | 1 | 2 |
| Opisthognathus | 2 | 5 |
| Pseudochromis | — | 8 |
| Cichlops and Pseudoplesiops | — | 2 |
| Sciænidæ | 44 | 43 |
| Sphyræna | 1 | 10 |
| Trichiuridæ | 6 | 5 |
| Caranx | 20 | 60 |
| Chorinemus | 4 | 7 |
| Trachynotus | 6 | 4 |
| Psettus | 1 | 2 |
| Platax | — | 7 |
| Zanclus | — | 1 |
| Equula and Gazza | — | 20 |
| Teuthis | — | 30 |
| Acanthurus | 3 | 42 |
| Naseus | — | 12 |
| Kurtidæ | 1 | 6 |
| Gobiodon | — | 7 |
| Callionymus | — | 17 |
| Batrachidæ | 5 | 4 |
| Tetrabrachium | — | 1 |
| Malthe | 1 | — |
| Petroscirtes | — | 30 |
| Clinus | 6 | — |
| Dactyloscopus | 1 | — |
| Malacanthus | 1 | 2 |
| Cepola | — | 1 |
| Gobiesocidæ | 5 | 1 |
| Amphisile | — | 3 |
| Fistulariidæ | 3 | 3 |
| Pomacentridæ | 17 | 120 |
| Lachnolæmus | 1 | — |
| Julidina | 36 | 190 |
| Pseudodax | — | 1 |
| Scarina | 21 | 65 |
| Pseudophycis | — | 1 |
| Bregmaceros | — | 1 |
| Ophidiidæ | 3 | 7 |
| Fierasfer | — | 6 |
| Pleuronectidæ | 21 | 56 |
| Saurina | 5 | 9 |
| Clupeidæ. | 33 | 84 |
| Chirocentrus | — | 1 |
| Murænidæ | 47 | 130 |
| Pegasus | — | 3 |
| Solenostoma | — | 2 |
| Syngnathidæ | 7 | 41 |
| Sclerodermi | 16 | 67 |
| Gymnodontes | 23 | 40 |
A. Shore Fishes of the Tropical Atlantic.
The boundaries of the tropical Atlantic extend zoologically a few degrees beyond the Northern and Southern Tropics, but as the mixture with the types of the temperate zone is very gradual, no distinct boundary line can be drawn between the tropical and temperate faunæ.
Types, almost exclusively limited to it, and not found in the Indo-Pacific, are few in number, as Centropristis, Rhypticus, Hæmulon, Malthe. A few others preponderate with regard to the number of species, as Plectropoma, Sargus, Trachynotus, Batrachidæ, and Gobiesocidæ. The Sciænoids are equally represented in both oceans. All the remainder are found in both; but in the minority in the Atlantic, where they are sometimes represented by one or two species only (for instance, Lethrinus).
B. Shore Fishes of the Tropical Indo-Pacific Ocean.
The ichthyological boundaries of this part of the tropical zone may be approximately given as 30° of lat. N. and S.; on the Australian coasts it should probably be placed still farther south, viz., to 34°; it includes, as mentioned above, the Sandwich Islands, and all the islands of the South Sea, but not the American coasts.
Some eighty genera of Shore fishes are peculiar to the Indo-Pacific, but the majority consists of one or a few species only; comparatively few have a plurality of species, as Diagramma, Lethrinus, Equula, Teuthis, Amphiprion, Dascyllus, Choerops, Chilinus, Anampses, Stethojulis, Coris, Coilia.
The Sea-perches, large and small, which feed on Crustaceans and other small fishes, and the coral-feeding Pharyngognaths are the types which show the greatest generic and specific variety in the Indo-Pacific. Then follow the Squamipinnes and Murænidæ, the Clupeidæ and Carangidæ families in which the variety is more that of species than of genus. The Scorpænidæ, Pleuronectidæ, Acronuridæ, Sciænidæ, Syngnathidæ, and Teuthyes, are those which contribute the next largest contingents. Of shore-loving Chondropterygians the Scylliidæ and Trygonidæ only are represented in moderate numbers, though they are more numerous in this ocean than in any other.