EDWIN CHAPIN STARKS 25 gill opening, a light stripe longitudinal along the posterior half of the side, which may be absent, and the fins are light straw-color. 78. Gymnotus carapo Linnzus.
Specimens were taken at Para and at Lake Papary. The following color note was made from a fresh specimen from the former locality. ‘The back is a very dark dusky-greenish-brown, shading through soiled sienna on the side to dusky-bluish below. The cross bars are black and the anal and pectoral are dusky.
Famity ELECTROPHORID.
79. EHlectrophorus electricus (Linnzus).
Two specimens were taken at Para. ‘They were dusky-yellowish-green above, growing yellow on the sides and bright yellow on the lower part of the head, while the lower part of the body was drab, growing lighter anteriorly and merging with the yellow of the head. Blended light spots, as big as the eye, were scattered over the body, and the margin of the vertical fin was light yellow.
Famity BUNOCEPHALID.
80. Platystacus cotylephorus Bloch.
A single specimen was taken at Para.
81. Aspredo aspredo (Linnzus).
Three specimens of this species were collected at Para. FAMILY SILURIDA.
82. Felichthys bagre (Linneus).
Three specimens were collected at Para. There is considerable variation among specimens of the same length in the length of the barbels. In two of them, 15 inches long, the maxillary barbel reaches to the end of the ventral in one, and to the end of the anal in the other. The mental barbel reaches nearly to the pectoral base in one, and scarcely past the eye in the other. The pectoral filament reaches past the tips of the middle caudal rays in one, and not to the caudal in the other. The pectoral filament reaches past the anterior fourth of the anal in one, and to the posterior fourth in the other. The interorbital bone cannot be described as flat in these specimens, for it is considerably convex.
26 FISHES FROM BRAZIL 83. Sciadeichthys proops (Cuvier and Valenciennes).
Two specimens were collected in the Para market, and one at Ceara. 84, Selenaspis herzbergii (Bloch).
This was by far the most abundant of the subfamily Tachisurine in the market at Para during our stay. The patch of teeth that develops behind the palatine patch and forms the “backward projecting angle” may be found in all stages of development. Sometimes it is not present at all; sometimes it forms a small disconnected patch; sometimes it is very large, connected with the palatine patch, and extends well back in the roof of the mouth. All intergradiations are present. It is not altogether a development of age or size as has been supposed, for it may be better developed in a specimen 8 inches long than in one a foot long, while other specimens of similar sizes, differing from these in no other manner, may or may not have it developed. However, it is usually best developed in large specimens, while specimens 7 or 8 inches long only occasionally have it. There is considerable variation in the roughness of the top of the head, and of the sharpness of the median ridge on the occipital process. One or two specimens were seen with a narrow but very evident groove running back from the frontal but not reaching to the occipital plate. 85. Tachysurus nuchalis (Giinther).
A few specimens were taken at Para which differ from the description of the type in having the maxillary barbels extend scarcely to the middle of the pectoral spine instead of ‘nearly to the end.” The tooth-patches on the palatines are the shape and size figured by Dr. Giinther, and the palatine teeth are coarse. The inner mandibular teeth are coarse and all of the teeth are brown-tipped. The gill membrane forms a distinct free fold across the isthmus, thus differing from Tachysurus spixt. 86. Pimelodina flavipinnis Steindachner.
Three specimens, from 12 to 15 inches in length, were taken at Para. The maxillary barbel in the large specimen reaches only to the end of the adipose dorsal, thus agreeing with Pimelodina nasus Eigenmann. In the other two it reaches to or a little beyond the caudal base, as described for Pimelodina flavipinnis. The length of the adipose fin is from 2% to 2% in the length, thus coming about between these two species. ‘The interorbital space is convex, and the head behind the eyes is not compressed as in Pimelodina nasus. The eye is contained about twice in the interorbital, or nearly midway between the condition described for these two species, as
EDWIN CHAPIN STARKS 27 is also the length of the pectoral as compared with the dorsal. In other respects (except “Die kopfbreite zwischen den kiemendeckeln erreicht 1% der kopflange,”” which is a mistake, as shown in Dr. Steindachner’s picture of the type) these specimens agree with Pimelodina flavipinnis. The eye in the head, the depth above the ventrals, the net-work of sensory tubes over the head, the distance of the adipose dorsal from the dorsal, and the color, with several rows of brown spots on the upper half of the body, all agree with thatspecies.
87. Pinirampus pinirampu (Spix).
Four specimens of this well-marked species were taken at Para. 88. Rhamdia sebe (Cuvier and Valenciennes).
A number of specimens were collected at Para. Comparing a specimen 6 inches in length collected in British Guiana by Dr. Eigenmann with these of equal size the eye is a little smaller, the body and caudal peduncle not so deep or so compressed, and the fontanel a trifle wider. 89. Rhamdia quelen (Quoy and Gaimard).
A couple of specimens were taken in the ponds at Ceara Mirim. The maxillary barbels do not reach to the middle of the adipose dorsal, but otherwise these differ only in minor characters from Rhamdia sebe and these are such characters that might be expected to intergrade in a sufficiently large series. It is probable that they represent only one species. 90. Pimelodus altipinnis Steindachner.
A common species in the market at Para, where several specimens were taken.
91. Pimelodus clarias (Bloch).
A couple of specimens collected by Dr. Baker and Mr. .Mann in the Rio Madeira about 400 miles from its mouth.
92. Brachyplatystoma filamentosum Lichtenstein.
A number of specimens of this species were collected at Para. 93. Brachyplatystoma vaillanti (Cuvier and Valenciennes). This species is a common one in the market at Para, where a number of specimens were collected.
94. Brachyplatystoma rousseauxii (Castelnau).
A half dozen specimens, from 11 to 14 inches in length without the caudal filament, were collected at Para. The following notes show some
28 FISHES FROM BRAZIL slight differences from the description published by Dr. Eigenmann (South American Nematognathi, p. 198), and add a few variations. The occipital crest reaches at least 34 of the distance from its base to to the dorsal spine. The eye is contained from 6% to 7% times in the snout; 34% to 4 times in the interorbital space; and 14 to 16 times in the length of the head. The maxillary barbel often reaches to the tip of the pectoral, and the postmental is usually coterminous with it, or sometimes is a trifle shorter. The upper lobe of the caudal bears a long filament, variable in length, but often as long as the entire body. The lower lobe is in one or two case filamentous and twice the length of the head, though usually it is but little produced or half that length. The vent is only 6 diameters of the eye from the anal. The entire side of the body is not reticulated and porous, but it bears a lateral band which is about half as wide as the interorbital space under the dorsal, grows a little wider anteriorly and tapers to a point posteriorly. ‘The head is contained from 3% to 3% times in the length.
In life it is a strikingly beautiful fish, with metallic golden red, coppery and silvery reflections.
95. Tenionema platynema (Boulenger).
A single specimen, 22 inches in length, was collected at Para. It is referred to this species, though in many of its characters it resembles as well T@nionema steeret EKigenmann and Bean, making it appear probable that the two are identical, as suggested in the original description of the latter species. The eye is contained 4 times in the interorbital space, 14 times in the snout, 20 times in the head, the adipose dorsal is 3 times as long as deep, and the ventral and pectoral are equal in length. All of these characters are as in 7. platynema. ‘The length of the head is 3 times as long as deep, and the length of the first dorsal ray is contained 114 times in the head as in 7. steerei. The depth of the body is 6% times in the length, and . the depth of the caudal peduncle is 2 times in its length. The fins and the sides are bright yellow in alcohol; its colors in life were not recorded. Platypogon,newgenus.
This genus is related to Brachyplatystoma, but has the barbels with their inner edges bearing a thin dermal membrane, and has not the characteristic small eye and flat, depressed snout. The teeth are freely movable and in broad bands. On the premaxillary, and to a less degree on the mandible, they grow longer posteriorly and point backward. ‘The palatine and vomerine teeth form a continuous band. The fontanel does not extend
EDWIN CHAPIN STARKS 29 back as a groove, and the top of the head is covered with a moderately thick skin. The supraoccipital process barely reaches to the dorsal plate. The adipose dorsal is situated over the anal and is about equal to it in length. The anal is emarginate and the caudal is forked.
96. Platypogon cerulorostris Starks, new species.
Plate 5.
The head is conical, as deep as wide opposite the posterior edge of the operculum, and equal to two-thirds of its length. It is contained 4 times in the length of the body to the caudal base. The depth of the body slightly exceeds its width, and is contained from 5% to 5% in the length. The depth of the narrowest part of the caudal peduncle is contained from 34% to 3% times in the head. The skin forms a moderately thick covering to the bones of the top of the head, forming a smooth surface with fine striations barely indicated. ‘The fontanel does not extend behind the eye, and a very short groove, not longer than the pupil, extends back and terminates abruptly. This is only made evident by removing the skin. The occipital process tapers back to a rather narrow point at the dorsal plate, being scarcely, or barely, in contact with it and not at all connected. The eye is large and round. Its diameter is contained 2% times in the interorbital space, 6 times in the head, and 24 times in the snout. The premaxillary band of teeth is widest at the middle, where it is equal to two-thirds of the diameter of the eye. The teeth grow long posteriorly and lie flat, pointing straight backward. The vomerine and palatine patches of teeth form a continuous band, a little narrower than the premaxillary band, and slightly narrower in the middle than at either side. All of the teeth are freely movable. The snout is convex above, and moderately broadly rounded in front. Its length is contained 3 times in the head. The rictus reaches to under the anterior margin of the eye. The barbels have a membraneous posterior margin, especially tle mentals and _postmentals, where the membrane is as wide, or a little wider, than the fleshy part of the barbel. The maxillary barbels reach to the base of the ventrals, the postmental barbels a little past the middle of the pectorals, and the mental barbels to the base of the pectorals.
The dorsal spine is filamentous, a third longer than the head, and reaches to the adipose dorsal. ‘The dorsal has 6 rays, and its base is contained 2%4 times in the space between it and the adipose dorsal. The base of the adipose dorsal is almost as long as that of the anal, and is situated directly opposite to it. Its vertical height is half of the length of its base.
30 FISHES FROM BRAZIL The anal has 14 rays, counting two in front of the longest ray. It is deeply emarginate, and its longest anterior rays reach past the tips of the last ones. The ventrals are situated a little less than the length of the head in front of the anal, and reach three-fourths of the distance to the anal. ‘The caudal is widely forked, and its lower lobe is a trifle the longer. Its longest rays slightly exceed the length of the head.
The ground color is slaty-brown on the back, grading downward to soiled white on the lower parts. On the upper part of the side two more _ or less definite rows of dark brown spots with blended edges, their diameter about half that of the eye. The top of the head is brown, with a conspicuous white spot over the fontanel. ‘The tip of the snout has a deep blue spot almost the exact color of modern blue-black writing ink. ‘The fins and humeral processes are deep orange-yellow, more intense on the caudal. Counting from the middle of the caudal fin downward the sixth to the eighth rays are abruptly black.
Three specimens were collected at Para, from 9 to 12 inches in entire length.
97. Sorubim lima (Bloch and Schneider).
A single specimen, 10 inches long, was collected by Dr. Baker and Mr. Mann in the Madeira River about 400 miles above its mouth. The plates on the head are finely striate, granulate, and separated by well-marked sutures. The anterior half of the occipital plate is bounded laterally by parietal and temporal plates. Its granulated surface does not reach to the dorsal plate, but below the thin membrane that covers it it extends to, and joins, the dorsal plate. The dorsal plate is spearheadshaped, with its point forward. The fontanel is open from the middle of the eye to within a diameter of the eye of the occipital plate, and anteriorly is represented as a groove to in front of the eye. A membraneous groove in the middle of the occipital plate appears like a second fontanel, but it does not pierce the bone.
98. Platystomatichthys sturio Kner.
Several specimens were collected at Para, the longest 14 inches in length. They show some variation from Dr. Eigenmann’s description. The projection of the snout beyond the lower jaw is contained from 2% to 2% in the length of the head. The eye is contained from 10% to 12% times in the same distance. In none of them are the palatine teeth as far remote from the vomerine, as described and figured by Dr. Eigenmann. Usually the palatine teeth are almost in contact with the vomerine teeth, there being
EDWIN CHAPIN STARKS Sill only a fine line of naked skin between. Occasionally the space is a little wider, but in none is it as wide as in the picture.
99. Doras dorsalis Cuvier and Valenciennes.
Many specimens of this common species were collected at Para. In most of them the stomach was tightly filled with a small univalve shell. The dorsal median plates and the ventral plates on the caudal peduncle are apparently never present in specimens as small as 5 inches in length, but in those 6 inches long some of them are present at least as rudiments. Though they are usually the best developed in the largest specimens they may be almost entirely absent. There is also much variation in the roughness of the head. In one specimen the bones of the head are so finely granular as to appear almost perfectly smooth.
These specimens show some slight variations from Dr. Eigenmann’s description (S. Am. Nematog. Cal. Acad. Sci.,1890). The caudal peduncle measured at the bases of the spines is as wide as deep. Usually a series of slight broken ridges extends from the frontal to the dorsal plate, and a well-developed groove on the dorsal plate extends to its tip, but only occasionally ‘“‘a marked groove extends form it [the frontal] to the tip of the dorsal plate.”” The pectoral spine is as long as the dorsal spine or often a trifle longer, and in the young of 6 inches in length it is equal in length to the head, or slightly shorter, but in specimens 10 or 11 inches in length it is considerably longer than the head.
100. Centromochlus heckelii (Filippi).
Several specimens of this peculiar little species were taken at Para, the largest 4 inches in length.
101. Trachycorystes galeatus (Linnzus).
Several specimens were collected in the market at Para. The following color notes were made from fresh specimens. The ground color is opaque, soiled light yellow, usually with black blotches scattered over the head, body and fins. These may be absent or often take the shape of horizontal elongate spots, or the form of irregular lines suggesting penciled lines. The under parts are milk-white, often more or less soiled with groups of small dark dots.
102. Trachycorystes striatulus Steindachner.
A few specimens were collected in the little ponds about Ceara Mirim. These much resemble Trachycorystes galeatus, but the head’ is not so rough
32 FISHES FROM BRAZIL or naked; the humeral process is shorter and does not project so much laterally at the base over the base of the pectoral spine; no pectoral pore is present; the top of the head between the eyes in the adult is a little flatter ; and in the specimens at hand the color is darker and the under parts dusky with fine points. These differ from the original description in having 2 or 3 fewer anal rays.
103. Pseudauchenipterus nodosus (Bloch).
A number of specimens from 6 to 9 inches in length were taken at Para, which I refer, with considerable hesitation, to this species, though they agree very well with the picture* and short description of Pseudauchenipterus guppy: Regan (Proc. Zool. Soc. 1906, Pl. XXIII). The head cannot be described as having the “upper surface, excepting the snout, rugose, not covered by skin; frontal bones not swollen.” On the contrary, the top of the head is as described by Dr. Eigenmann (S. Am. Nematognathi, p. 290) for P. nodosus, with the frontals swollen and of distinctly “honey-comb structure.” It is covered with thin skin. ‘These specimens have the color markings as described and figured for P. guppyi, with the same light lateral band and vertical row of lhght spots, and with or without the black border to the caudal. These markings are occasionally obscure, though they are usually very conspicuous. They differ from Dr. Eigenmann’s description of P. nodosus as follows: ‘The pectoral spine is usually sharp-pointed and does not end in a filament. Its length is from 4 to 434 (not from 224 to 34%), thus agreeing with the pictures published by Bloch and by Bleeker. The humeral process usually extends to the middle of the pectoral spine or a trifle beyond.
104. Auchenipterus nuchalis (Spix).
Very common at Para, where a large number were collected. There is a remarkable variation in the maxillary barbel. In most of them the barbel extends straight back under the eye. It is very slender, its anterior end ossified, and it fits into a shallow groove immediately below the eye. In the opposite extreme the base of the barbel is a wide curved bone, much wider than the pectoral spine, and its curve forms at least a fifth of a complete circle (though it is not an even curve, being more abrupt below the eye). It extends upward from the eye, and ends above the level of the eye a little behind the head. It does not taper much posteriorly, but ends * The title of the picture and the reference in the text are transposed with those of P. pasee.