156 Bulletin 47, United States National Museum. 



expanded beneath the temporal plate, usually communicating with the 

 outside air at a notch in the posterior margin of a temporal plate or 

 sometimes by many holes in the temporal plate; strong movable bones or 

 ribs extending from near the posterior end of the coalesced vertebraj out- 

 ward; these compressed and sometimes forked at base; these structures 

 form a more or less complicated arrangement which gives fixity to the 

 dorsal spine, but prevents a lateral motion of the head. A large family 

 of small and singularly armed catfishes, chiefly confined to the rivers of 

 South America; 24: genera and 247 species are described by Dr. Eigen- 

 manu, Avho is the most recent authority on this group. (Silurid.e Hypos- 

 TOMATINA in part, Giinther, Cat., V, 221-260). 



Loricariina: ; 

 a. Tail long, tapering posteriorly, with a single series Of plates on the sides. Dorsal fm usu- 

 ally inserted behind the origin of the ventrals; no adipose fin. Intestinal canal usu- 

 ally not longer than body. Upper caudal lobe sometimes produced. 

 6. Dorsal fin inserted above or slightly behind anal; 2 to 5 plates between it and occipital 

 process. Eyes superior. Tail with strong lateral keels. Snout not expanded at 

 tip nor margined with spines. Loricaria, 84. 



Hypostominje : 

 aa. Tail short, compressed or rounded. Lips entire. Adipose fin usually present; ventral sur- 

 face naked, or covered with minute granular plates. Intestine greatly elongate, 

 many times as long as the body; lower caudal lobe sometimes produced. 

 0. Temporal plate not perforate. 



d. Margin of the snout granular, with sonu-times a naked spot at tip. Scutes on 

 lower surface of tail exposed. Dorsal rays I, 7; or I, 8. Teeth fine and 

 numerous. 

 e. Interopercie with erectile spines borne on a movable plate. Dorsal and anal 

 distinct. Hemiancistru.'!, 85. 



cc. Margin of the snout naked, without bristles, granules, or tentacles. Interopercie with 

 erectile spines. Cn.ETOSTOMrs, 8fi. 



txc. Margin of the snout with tentacles, or, in the female, sometimes naked. Ventral sur- 

 face naked. Interopercie with a bunch of spines inserted on a movable plate. 



Ancistrus, 87. 



84. LORICARIA, Linnaius. 



Loncano, ILinNjT.us, Syst. Nat., Ed. x, 1758, 307, (cataphracta). 



Sturisoma, Swainson, Nat. Hist. Fishes, 11, .304, 1839, (roslrala). 



nemiodon,Ksr.R, Panzerwolsc, 89, 1853, (ilepressus). 



LoHcariichthjs, Blef.ker, Nederl. Tijdschr. Dierk., 80, 1803, {dnra = cataphracta). 



Pseudoloricarin, Bleeker, /. c, 80, (Ixvutscida). 



Parahemiodnn, Bleeker, I. c, SO, {typiis). 



llemioloricaria, Bleeker, /. c, 81, (caracase»si<<). 



Pseudohemiodotiy Bleeker, I. c, 81, {platycephalua). 



Eineloricaria, Bt.eeker, I. c, 81, (lima). 



Oxyloricaria, Bleeker, I. c, 81, (barbata). 



This genus, sufficiently characterized in the analytical key above, con- 

 tains a very large number of species, abounding in the rivers in the east- 

 ern part of South America. They are remarkable for their elongate form 

 and for the coat of mail which covers the body. A few of these extend 

 northward to the waters about Panama. There is considerable variation 

 in form amoug these fishes, but the different groups inin into each other 

 and are best regarded as subgenera, (lorica, a cuirass, or coat of mail.) 



