EQUATORIAL ZONE. 279 



only ; comparatively few have a plurality of species, as 

 Diagramma, Lethrinus, Equida, Teuthis, Amphiprion, Das- 

 cyllus, Choerops, Chilinus, Anampses, Stethojulis, Coris, Coilia. 

 The Sea-perches, large and small, which feed on Crusta- 

 ceans and other small fishes, and the coral-feeding Pharyn- 

 gognaths are the types which show the greatest generic and 

 specific variety in the Indo - Pacific. Then follow the 

 Squamipinnes and Murcenidce, the Chipeidm and Carangidce 

 families in which the variety is more that of species than of 

 genus. The Scorpmiidcc, Pleuroncdidce, Acronuridce, Scimnidm, 

 Syngnathidcc, and Teuthyes, are those which contribute tlie 

 next largest contingents. Of shore-loving Chondropterygians 

 the Scylliidm and Trygonidcc only are represented in moderate 

 numbers, though they are more numerous in this ocean than 

 in any other. 



C. Sliore Fishes of the Pacific Coasts of Tropical America. 



As boundaries within which this fauna is comprised, may 

 be indicated 30° lat. N. and S., as in the Indo -Pacific. 

 Its distinction from the Indo-Pacific lies in the almost 

 entire absence of coral-feeding fishes. There are scarcely any 

 Squamipinnes, Pharyngognaths or Acronuridte, and the 

 Teuthyes are entirely absent. The genera that remain are 

 such as are found in the tropical zone generally, but the 

 species are entirely different from those of the Indo-Pacific. 

 They are mixed with a sprinkling of peculiar genera, consist- 

 ing of one or two species, like Discopyge, Hoplopagrus, Doy- 

 dixodon, but they are too few in number to give a strikingly 

 peculiar character to this fauna. 



Three districts are distinguishable : — 



a. The Central American district, in which we include, for 

 the present. Lower California, shows so near an affinity to the 

 tropical Atlantic that, if it were not separated from it by the 



