9 
the mixture with the types of the temperate zone is very gradual, 
no distinct boundary line can be drawn between the tropical and 
temperate faunee. 
“ Types almost exclusively limited to the tropical Atlantic, and 
not found in the Indo-Pacific, are few in number, as Centropristis, 
Rhypticus, Hamulon, Malthe. A few others preponderate with 
regard to the number of species, as Plectropoma, Sargus, Trachy- 
notus, Batrachide, and Gobtesocide. The Scienoids are equally 
represented in both oceans. All the remainder are found in 
both, but in the minority in the Atlantic, where they are some- 
times represented by one or two species only (for instance, 
Lethrinus).” 
It would seem that— 
“ As with fresh-water fishes, the main divisions of the shore- 
fish fauna are determined by their distance froni the equator, the 
equatorial zone of the fresh-water series corresponding entirely to 
that of the shore-fish series.” 
Although as regards the latter, the fauna is more extended 
north and south in its distribution from the equator. 
Dr. Giinther’s ‘ Study of Fishes’ affords, from page 275,a 
list which, although only containing the principal genera or 
groups of coast-fishes, in the Equatorial zone, yet admits of 
the formation of an opinion on the affinity of the Tropical 
Atlantic and Indo-Pacific, and to it, for more detailed in- 
formation generally in what I have ventured to extract, I 
would beg leave to refer my hearers. 
There are included in the list ninety-six families or 
groups of shore-fishes in connection with the Tropical 
Atlantic and the Indo-Pacific, in the proportion of 59 to 87, 
and although these are not specimens of each genus com- 
mon, yet the proportion of the species stands as 532 to 1917. 
Pelagic fishes, viz., fishes inhabiting the surface of mid- 
ocean, like shore-fishes, are most ‘numerous in the tropical 
zone, and with few exceptions—Lchinorhinus, Psenes, 
