of the Island of Trinidad, IF. /. 5 



in more detail, and those representing new genera will be fully 

 illustrated. 



With the intention of rendering this memoir more useful to 

 the inhabitants of Trinidad, and to lacilitate the identification 

 of the fishes described, we have given the popular names, when- 

 ever they have been ascertained, by which the species or groups 

 of allied species are known in the island ; but there, as in almost 

 every country, only the larger and more remarkable species 

 have had such names bestowed on them. As is almost univer- 

 sally the case among those who are unlearned in zoology, most 

 of the rare and small species have no vernacular names, the lat- 

 ter being generally regarded as the yonng of larger ones, and 

 all the species of a genus, when there is not a marked difierence 

 in color or some trenchant peculiarities, are confounded under a 

 single specific name. 



lY. 



In the early part of the present year, a work was published 

 by Dr. L. A. A. De Yertenil, a physician of considerable attain- 

 ments residing in the island, on " Trinidad ; its geography," &c. 

 To this volume there is an appendix on the " ISTatural history of 

 Trinidad," the zoological portion of which contains a chapter on 

 the " Mammalia," and a catalogue of the indigenous species, by 

 the author of the volume ; " an essay on the Ornithology of 

 Trinidad, by Antoine Leotaud, M.D.P. ;" a " catalogue of rep- 

 tiles by Dr. J. Court," and one of fishes by Dr. Leotaud. The lat- 

 ter is stated to " exhibit nearly all the genera which may be said 

 to belong to the island ;" it will be observed what reliance this 

 statement is entitled to, on a comj)arison of his catalogue of the 

 genera represented by fluviatile species with those given in our 

 synopsis. We had almost determined to pass it over in silence, 

 but on subsequent reflection, it was deemed advisable to call 

 the attention of naturalists to it and to correct its errors, in 

 order that none should imbibe false views on the subject of the 

 geographical distribution of groups and the habits of species, 



