318 REPORT OF COMMISSIONER OF FISH AND FISHERIES. [94] 
in some details of structure, and their real relations are with Apion- 
‘ichthys. Achiropsis differs from Apionichthys chiefly in the develop- 
ment of the left ventral fin. This is rudimentary in Apionichthys and 
perfect in Achiropsis. 
6 
ANALYSIS OF SPECIES OF ACHIROPSIS. 
a. [Gill-opening on both sides present, but reduced to a short slit as long as eye next 
to the upper end of the opercular margin ; eye very small; snout with a proboscis- 
like prolongation beyond the mouth; blind side anteriorly covered with fringes, 
but without true scales; scales on body ctenoid; fins scaly. Dorsal and anal 
fins slightly joined to the caudal; ventral of right side continuous with the anal. 
Body oblong. Color grayish brown. Head 5 in length; depth 2}. D, 82. A. 
61. V.5-5. P.0., 37 to 40 scales in an oblique series above lateral line.] (Stein- 
TAGE) ASSO O aa one essa oe eeeasice Ga aec GaSeee bbe: NATTERERI, 121. 
aa. Gill-opening of eyed side wanting, the gill-membrane being throughout adnate to 
the shoulder-girdle ; gill-opening of blind side an oblique slit just below posterior 
angle of opercle, its length 4} in head. Eyes small, close together, the upper 
considerably in advance of lower, their diameter equal to the interorbital width ; 
snout protruding over the mouth, proboscis fashion, making the anterior profile 
aregular curve. Snout 2? inhead. Scales small (larger than in A. natiereri), not 
as rough as in Achirus, those on the blind side of the head wanting anteriorly, 
their place taken by cirri and fringes of moderate length; lateral line distinct, 
straight; fin-rays scaly; lower lip slightly fringed on eyed side, not on blind side. 
Nostril as in Achirus, around foramen in front of interorbital space, not produced 
into a tube. Dorsal beginning on the snout, the dorsal and anal slightly joined 
to the caudal; ventral fin beginning at the chin, in front of the isthmus, the tip 
of the snout being in contact with its first ray; ventral of right side with ex- 
tended base, wholly continuous with the anal; left ventral lateral, normally 
placed, its five rays opposite the 3d, 4th, and 5th rays of the right ventral; no 
pectoral fins. Body oblong, less deep than in Achirus. Color sand-color, with 
faint traces of about 8 narrow cross-bands; body and fins profusely and finely 
mottled and speckled with darker. Head, 44; depth, 24. D. 60. A. 44. V. 5-5, 
P. 0. Scales 70, about 28 in an oblique series above lateral line. 
ASPHYXIATUS, 122. . 
121. ACHIROPSIS NATTERERI. 
Solea (Achiropsis) nattereri Steindachner, Ichth, Beitriige, v, 110, 1876 (Rio Negro). 
Habitat.—Rivers of Northern Brazil. 
We know this species from Steindachner’s description only. 
122. ACHIROPSIS ASPHYXIATUS. 
Achiropsis asphyxiatus Jordan, sp. nov. (Goyaz, Brazil). 
Habitat.—Rivers of Brazil. 
The type of this species is a female specimen in good condition, 4% 
inches long (11106 M.C, Z.), from Goyaz, Brazil. It differs from all other 
flounders in having but a single gill-opening. Possibly this character 
is only accidental in the individual, and that a small gill-opening may 
normally be present on both sides. . It is certainly not present on the 
eyed side in the typical example, 
