2 U. 8. p. R E. EXP. AND SURVEYS ZOOLOGY — GENERAL REPORT. 



The Pomacentrid family, or raariue labroids, with pectinated scales, has given us one species, 

 which we have placed in the genus GlypJiisodon, not having the means of determining it more 

 accuratel}'. 



The Chromids, or fresh water labroids, with pectinated scales, have not yet been met with 

 along the Pacific range of North America. We have evidences of their presence in the basin 

 of the Rio Grande del Norte (Rio Bravo), one species of which being figured and described in 

 the "Report on the United States and Mexican Boundary Survey." 



The Scomberesocids, on the other liand, are represented, so far, by a species of the genus 

 J3 clone. 



The Gadoid family has given us a cod, a whiting, and a cusk ; the latter we have not examined. 



The Pleuronectids, or flat-fishes, are tolerably well represented, tliough we observe as yet no 

 turbots {Rhomhws), properly so called. The halibut (Hippoglossus) is spoken of as occurring 

 along the coast, but we have not examined it as yet. 



The Ophidioid family is represented by two known genera, Ojohidion and Ammodytes, whilst 

 the true eels have not yet been heard of. 



The Salraonids are rather abundant, especially in species of the Linnean genus Sabno, to 

 which may be added a white-fish {Coregonus) and two smelts, properly so called [Osmerus and 

 ThahkhUujs). 



No Characinids are known north of the valley of the Rio Grande del Norte, (Rio Bravo), where 

 one species was collected by the United States and Mexican Boundary Commission, and in 

 whose report it is figured and described. 



The Scopelids have furnished us, so far, with one species of the genus Saurus along the 

 Pacific coast. 



The fresh waters teem with Cyprinoids and Percoids, the former east and west of the Rocky 

 Mountains, the latter only eastwardly, in the shape of sun-fishes (Fornotis) and bass (Ambloplitea 

 and Centrarchus) , a single species of the bass having been met with in California. 



Of the Cyprinodont family we have mentioned but one species, an inhabitant of the fresh 

 waters of California. Those collected in the interior of the continent we propose to investigate 

 at some future time. 



The Etheostomoids are likewise left aside for the present. 



A few pickerels or Esocids have been observed in the Hydrographic basin of the Arkansas. 



A few catfishes (Fimelodus) were procured at the initial point of the exploration of the 35th 

 and the 47th parallels ; none having been found west of the Rocky Mountains. 



Of the herring family, we meet with two herrings {Clupea and 3Idetla), and several anchovies 

 (Engrmdis), but as yet no shads (Alosa) have been seen in the collections made. 



The Plectognaths have furnished a Balisles and a balloon-fish. 



The Lophobranchs are represented by a few pipe-fishes and a sea-horse. 



The Ganoids of the western coast consist of sturgeons, of which peculiar forms are met with 

 in the fresh waters of the interior of the continent, where we find also a few mud-fishes, and 

 have obtained some gar- pikes. 



The cartilaginous fishes, so far as observed, are anything but numerous; a few sharks, skates, 

 and lampreys constitute the list we are for the present acquainted with. Amongst sharks and 

 skates there are curious genera: Ceslracion, Triakis ; Ehinohatis, Uraptera, and Rhinoptera, 

 whilst amongst lampreys we meet the ordinary genera, Petromyzon and Ammocoetes. 



The elephant-fish {Chimaera) was also observed as far as Puget's Sound. 



