:PisHES. 23 



screaming, and soon after betake them, with all the 

 swiftness of their own sharp wings, towards the shore : 

 then also may the observer feel the effect of a tropical . 

 atmosphere, by the intenseness of his head-ache; 

 and as he turns towards home first discover that the 

 mountains inland are charged with clouds, and vivid 

 lightnings are playing around them. In vain has he 

 stood in the shade of an umbrella, which now again 

 is to skreen him from the night dews. If his return 

 be by means of a canoe, the night become dark, and 

 his course be through creeks among the mangroves, 

 his weaned attention will still be revived by the 

 myriads of small fish springing about in all directions, 

 some generally mullets, leaping even within board, 

 and, if silence be preserved, he may on some occasi- 

 ons be surprised by the noise of an alligator, closing 

 his jaws as if it were the fall of a trap door. But to 

 return to our subject. 



Where shoaUng waters have sandy bottoms and 

 form valleys, from sixty fathoms upwards, Trunk fish 

 and Expansile Diodons are frequent; and where 

 banks of about forty fathoms occur, particularly in 

 temperate regions, many species are met of those 

 families, whose heavy bony heads require ventral 

 fins beneath the throat, and indicate that their habi- 

 tual position in the deep is with the head downwards, 

 grovelling for bivalves ; here also we may find their 

 particular enemies, and the deep water flat-fish^ 

 forming assemblages of all the Gadoid (cod-fish) 

 families, together with Chimceras, Bogmari, Anarhi- 

 cas, Hippoglossi, ground sharks, dog fish, and other 

 squali, v/ho only forsake this kind of prey to follow 

 the columns of Clupese (herring) which in their sea- 

 son are seen advancing above these plains, coming 

 from the polar seas to fulfil their destinies along the 

 coasts and estuaries of more genial climates. From 

 more sunny seas other columns come also to the 

 temperate latitudes, such as the genera of Scomber 

 and Mugil (Mackerel and Mullet), but the former 

 make a longer stay and come closer in with the 



