2 
U S. P. R. R EXP. AND SURVEYS—ZOOLOGY—GENERAL REPOhT. 
which we have placed in the genus Glyphisodon, not having the means of determining it more 
accurately. 
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 Eio Grande del Norte or Rio Bravo, figured and described in Major Emory’s “ Report on 
the United States and Mexico Boundary Survey.” 
The scomberesocids, on the other hand, are represented, so far, by a species of the genus 
Belone. 
The gadoid family has given us a cod and a whiting. 
The pleuronectids, or flat fishes, are tolerably well represented, though we observe as yet 
neither turbots ( Rhombus ) nor halibuts (Hippoglossus). 
The ophidioid family is represented by two known genera, Opliidium and Ammodytes, whilst 
the true eels have not yet been heard of. 
The salmonids are rather abundant, especially in species of the Linnean genus Salmo, to 
which may be added a white fish ( Coregonus ), and two smelts, properly so called ( Osmerus and 
Argentina). 
No characini are known north of the valley of the Rio Grande del Norte (Rio Bravo), where 
one species was collected by the United States and Mexico Boundary Commission, and in whose 
report it will be figured and described. 
The scopelini have furnished us, so far, with one species of the genus Sauriis or Laurida 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 ( Pomotis ) and bass, ( Centrar- 
elms,) 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. 
Neither pikes, nor pickerels, or esocids have been observed west of the Mississippi valley. 
A few catfishes ( Pimelodus) 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 a true herring ( Meletta ), and two anchovies (Engraulis), 
but as yet no shads ( Alosa ) have been seen in the collections made. 
The lophobranchs are represented by a few pipe fishes. 
So much for the osseous fishes. The cartilaginous, so far as observed, are anything but 
numerous ; a few sturgeons, sharks, skates, and lampreys constitute the list we are for the 
present acquainted with. Amongst sharks and skates there are curious genera: Cestracion, 
Triakis, Rliinobatis, and Rliinoptera, whilst amongst lampreys we meet the ordinary genus 
Petromyzon. 
