1868.] DR. A. GUNTHER ON NEW AMERICAN FISHES. 235 



length of the head (to the occiput) is contained thrice and one- 

 fourth in the total (without caudal). The margin of the snout is 

 rough, like the upper surface of the snout. Structure of the mouth 

 and teeth as in Plecostoimis. Teeth small, about ten on each side 

 in the upper jaw, and thirteen in the lower ; lips narrow. The 

 lower side of the head is naked, except where it is covered by the 

 large subsemicircular iuteroperculum. Scutes without keels, covered 

 with fine spines, which are arranged in longitudinal striae. Thorax 

 covered by two pairs, abdomen by three series of broad scutes. 

 Dorsal fin much higher than long, the length of its base being one- 

 half of its distance from the adipose spine ; caudal fin obliquely 

 truncated, the lower ray being much longer than the upper. Pec- 

 toral spine serrated along both edges, extending beyond the middle 

 of the ventral ; ventral fin scarcely extending to the anal. Colora- 

 tion uniform olive, caudal fin darker. 



A single example, 3 inches long, was obtained by Mr. Bartlett at 

 Xeberos. 



LORICARIA ROSTRATA, Spix. 



The figure given in Spix's Pise. Bras, is bad. The figure of 

 Valenciennes under the name of Loricaria acuta (pi. 452) has 

 probably been made from an example of this species ; it certainly 

 does not agree with his description of L. acuta. This species 

 shows the same sexual character as Plecostomiis barbatus, the male 

 having a bearded snout. Kner, not being aware of this, described 

 the female as L. rostrata, and the male as L. barbata. Mr. Bartlett 

 found this fish at Xeberos. 



Loricaria lanceolata. (Fig. 3, p. 236.) 



Head and body much depressed, but narrow, the greatest width 

 of the head being three-fifths of its length. Lower lip broad, 

 slightly notched behind; lateral barbels fine and small; fringes of 

 the lip indistinct. Teeth very fine, few in number, about five on 

 each side in the upper jaw, and about seven in the lower. Orbit 

 with a rather shallow notch behind, its horizontal diameter (the 

 notch included) being two-thirds of the width of the interorbital 

 space, which is flat. Head and body rough ; a pair of obtuse 

 ridges on the occiput and nape. The lateral ridges of the body are 

 confluent on the fifteenth scute. L. lat. 28. There is a series of 

 seven scutes between the roots of the pectoral and ventral fins. 

 Thorax and abdomen covered with irregular scutes. The length of 

 the head (measured to the occiput) is a little more than one-fifth 

 of the total (without caudal). None of the fin-rays are much pro- 

 duced ; the pectoral extends somewhat beyond the origin of the 

 ventral. Origin of the dorsal fin opposite to the root of the ventral. 

 Brown ; back with about five obscure dark cross bands ; fins with 

 broad, irregular confluent black cross bands. 



One specimen, 3| inches long, was found by Mr. Bartlett at 

 Xeberos. 



