708 The American Naturalist. [August,. 
ZOOLOGY. 5 
An Australasian Sub-family of Fresh-water Atherinoid - 
Fishes.—Mr. J. Douglas Ogilby, of the Australian Museum, of Syd- 
ney, has recently sent me a photograph and description of a new 
species of a genus called Aristeus by Castelnau. This genus is of 
much interest from a morphological as well as geographical point of 
view. Mr. Ogilby has asked, “Is it an Atherinid and allied to 
Nematocentris ? or should a new family be formed of it?” Mr. Ogilby, 
unlike the original describer, is quite happy in his appreciation of its 
affinities. 
The genus Me/anotenia was proposed by Gill in 1862 (Proc. Acad. 
Nat. Sci. Phila. 1862, p. 280) for a fish called Atherina nigrans by 
Richardson, and was subsequently renamed Nematocentris (Peters, 
1866), Strabo (Kner & Steind, 1866), and Zantecla (Cast., 1873). It 
has been generally referred to the Atherinide, but Kner and Stein- 
dachner were disposed to associate it with Pseudomugil in their family 
Pseudomugilide, and Castelnau proposed a new family, Zanteclide, for 
it. No satisfactory family characters were given. 
The genus Aristeus was described by Castlenau in 1879, and by him 
referred to the family Gobiide. Steindachner, in a notice of the 
genus (Zool. Jahresber. 1879, p. 1061), happily hit at its relations i in 
the words, “Aristeus N. G. Casteln. (wal 
d. Ref.).” : 
There are two specially interesting features of these genera. 
(1) They deviate from the typical Atherinids in the elongated anal 
fin which advances far forward, and with the advance are coordinated 
an advanced position of the anus and of the ventral fins, whose roots are 
little behind the bases of the pectoral fins. 
(2) The species of both genera are confined to the fresh-waters of the 
Australasian realm and the constituent group is thus one more of the 
groups limited to a single realm. 
The deviations of the genera from the typical Atherinide appear to 
be sufficient to warrant their segregation in a peculiar sub-family 
which may be named Melanoteniine. But confirmation by anatomi- 
cal characters are very desirable. The sub-family may be defined pro- 
visionally, as follows ; 
MELANOTÆNIINÆ. Atherinids with a spinous dorsal, whose fore- 
most spine is robust and rest weak, a very long anal, and thoracic 
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