1894.] Zoology. 611 
D. 10; A. 20-23; head 3}; depth 33, eye in the head 23 and once 
in the inter-orbital; scales 32-34, the lateral line incomplete, only 6 
scales perforated. 
Maxillary toothless, extending nearly to the centre of the pupil of the 
eye. The dark-brown lateral band, deepest colored anteriorly, edged 
above with a conspicuous silvery band. No caudal spot. Dorsal 
about midway between the tip of the snout and base of the caudal, and 
over the space between the anal and ventral. Anal with first six rays 
elongate. Many specimens from Brazil. Length 10-29 mm. 
2. Tetragonopterus paucidens. Related to T. diaphanus Cope from 
which it differs in having 1 to 3 maxillary teeth; in proportions and 
in lateral markings. 
Head 33; depth 23, in the length. Snout 33, diameter of the eye 3 
in the head. The maxillary extends to the anterior border of the 
pupil. A silvery lateral band and a diffuse caudal spot present. No 
humeral spot. 
D. 11; A. 19; scales 5-31-3; lateral line complete. Length 45 mm. 
One specimen from Itaituba, 45 mm. long. 
3. Tetragonopterus santaremensis. This species has much the appear- 
‘ance of T. bellottii Steindachner: The scales of the lateral line are 
perforated to the base of the caudal while in T. bellottii only 5 to 7 
scales are perforated. The caudal spot is somewhat more rhomboidal 
and extends to the end of some of the rays, otherwise the lateral band 
and humeral spot are about as in T. bellottii. 
Head 3? ; depth 31 in the body. D. 10; A. 20-22; scales 5-30-3. 
Anterior dorsal and anal rays elongate. Snout short, 4 in the head. 
Maxillary toothless, extends to the eye. Diameter of the eye somewhat 
more than the width of the inter-orbital and 21 in the head. 
Ten specimens from Santarem, 8-24 mm. lon 
4. Tetragonopterus astictus. Related to T. Kiwis Günther. It 
differs from that species in having no caudal or humeral spot, no red 
margins on the anal and ventral fins and fewer rows of scales. 
Head 33, depth 34, in the length. Eye 23 in the head and once in 
the inter-orbital space. A silvery lateral band present, most distinct 
posteriorly. 
Lateral line complete, scales 5-35-33. D.10; A.30. Maxillary 
toothless, extending a little past the anterior margin of the orbit. 
One specimen 53 mm. long from Brazil. 
5. Aphyocaraz maxillaris. Maxillary with minute teeth along its 
entire margin. Intermaxillary with about ten teeth, the inner four 
three-pointed. Mandible with a few conical teeth in front. 
