438 



GEOGRAPHICAL ZOOLOGY. 



[PART iv. 



these, except the last, are confined to the Mediterranean and the 

 Atlantic as far as Madeira.- Eight other genera are characteristic 

 of the Atlantic, most of them being West Indian, but one from 

 the coasts of North America. Seven genera are common to all 

 the great oceans ; the remainder being confined to the Indian 

 and Pacific Oceans, ranging from Japan to New Zealand, but 

 being far more abundant between the Tropics. 



FAMILY 50. EMB^QTOCIDJE. (2 Genera, 17 Species.) 



" Marine viviparous fishes, with compressed elevated bodies 

 covered with cycloid scales, and with small teeth." 



DISTRIBUTION.; Pacific Ocean from Japan and California 

 northwards. One species enters the fresh waters of California. 



FAMILY 51. GERRIDJE. (1 Genus, 28 Species.) 



" Marine fishes, with compressed oblong bodies covered with 

 minutely serrated scales, and with small teeth." 



DISTKIBUTION. Tropical seas ; ranging south as far as the 

 Cape of Good Hope and Australia, and north to Japan and 

 (one species) to New Jersey, U.S. 



FAMILY 52. CHROMID^E. (19 Genera, 100 Species.) 



" Fresh-water herbivorous or carnivorous fishes, with elevated 

 or elongate scaly bodies, and small teeth." 



DISTRIBUTION. The Oriental, Ethiopian, and Neotropical re- 

 gions. 



E-titroplus (2 sp.) is from the rivers of Southern India and 

 Ceylon; Chroniis (15 sp.), Sarotherodon ' (2 sp.), and Hemi- 

 chromis (4 sp.), are from the rivers and lakes of Africa, ex- 

 tending to the Sahara and Palestine. The remaining 15 genera 

 are American, and several of them have a restricted distribution. 

 Acara (17 sp.) inhabits Tropical South America and the 

 Antilles; Theraps (1 sp.), Guatemala; Heros (26 sp.), Texas and 



