Cope.] ‘s 698 [May 17, 
GENERAL OBSERVATION. 
The 121 species enumerated in the preceding pages are distributed 
among the following natural families. 
SHAOGO RAN aon Sap oucar aso cco On icidG Sone SL Re 
ELypopluthal midees 2. ise Be lo AE aided ed alee attelayeterc cusses esa 
Siluride...... Els foee ote tabet eta tee) a= ites eh fa) ae she lta a fete ete Ae eich eee ee a 
AS PLECINIG:..; «i sicivevete isha Peele Shetees oleig ANT bees teois tals Atta ctw ches Ream 
Sternopygide..... seman senos em daperetue sons ssitoreyetslovs Greate ta: slacttiehithe hee) 
Characinide...... ree eer ay HATS oes ae OUI Ae ne Me Tatra Sereecr cay 
Osteoglosside. -%/- 1s. sk e Otsbaheiaraiaieie he elocal Wheto Nee peiere terest ches evelele Cheha te aan 
Cy prin odonbidles 6/2). 2/01 holiest be che de's/atae nie eslsll= San areleaieenee siante eel 
Belonideseeame ctv inteese eke co seisr Sintec d Shittu sa. tee cca 
MetrodontiGee spec rise siae oe btostio nd anOC OU aD Gate AAO. Bi Sisteve ions ae al 
Chromuidideesrrtctetsmereiel er cia SieiSeiaterdisetont oe Me ofe aie bcleis letevan Sicks Soe melee 
121 
The preceding families have all been known heretofore as occurring 
in the fresh waters of South America, so that an analysis of the contents 
of this catalogue must relate chiefly to the genera and species. In so 
doing I first point out two genera whichare characteristically marine, which 
have been shown by Giinther and Steindachner to inhabit the Brazilian 
Amazon. Ihave proven that their distribution extends even to the Pe- 
ruvian Amazon, 2500 miles from the sea. They are : 
I. Belone L. Tetrodon L., represented by one species each. 
I next enumerate four species which are confined to the Alpine waters 
of the Amazon, having been brought by Prof. Orton from the elevations of 
from 10,000 to 11,400 feet. These are : 
II. Arges sabalo, C. V. 
Trichomycterus dispar Tsch. 
Trichomycterus gracilis C. V. 
etragonopterus tpanquianus Cope. 
These represent the two families of Siluride and Characinide, which 
are distributed everywhere in the neotropical realm. Of the Characi- 
nide, Tetragonopterus is universally distributed. Of the Siluride, Arges 
is Alpine, but whether found in the waters of the Pacific Slope as well 
as the Atlantic, I am not informed. The other genus, Trichomycterus, 
is Alpine and West Coast, occurring from Equador to Southern Chili. 
The two species enumerated above are the only ones from Atlantic 
waters yet known. This is one of the few cases where a West Coast form 
crosses the great water-shed. It is well known that many genera are 
common to the waters of both coasts, and even, according to Giinther, the 
species Mucrodon trahira. 
I next note the genera which have so far not been found on the lower or 
middle Amazon, and which may be regarded as characteristic of the Peru- 
