MALACOFTERYGIl AimOMINALES. 221 



more strongly dentated than that of any other Silurus; there is but 

 one dorsal on the anterior part of the back, the first ray of which is 

 not very strong; the anal, on the contrary, is very long, and extends 

 under the whole of the tail, which is long and slender. 



But few species are known, and they have six or eight cirri; 

 it is somewhat remarkable, that when the latter number prevails, 

 one pair is attached to the base of those on the maxillaries; the 

 four of the lower jaw are disposed in pairs, one behind the 

 other.(l) 

 Some of them are found with globules, which appear to be their 

 eggs, adhering to the thorax by pedicles. 



LoRicAHiAj Lin. 



So called on account of the angular and hard plates in which the 

 head and body are completely mailed. These fishes are otherwise 

 distinguished from the mailed Siluri, such as the Callichthys and 

 the Doras, by their mouth which opens under the snout. This mouth 

 is most analogous to that of a Synodontis; small intermaxiUaries sus- 

 pended under the snout, and transverse disunited mandibularies, sup- 

 port long, slender, and flexible teeth, terminating in a hook; a broad, 

 circular,membranous veil encircles the opening, and the pharyngeals 

 are furnished with numerous teeth, en pave. The true opercula are 

 immovable, as in Aspredo, but two small, external, movable plates, 

 appear to supply their place. There are four rays in the membrane. 

 Strong spines constitute the first rays of the dorsal, pectorals, and 

 even of the ventrals. They have neither caeca nor natatory bladder. 

 They may be divided into two subgenera. 



HyposTOMus, Lacep. 



A second small dorsal furnished with a single ray as in Callich- 

 thys; the labial veil simply papillate, and provided with a small 

 cirrus on each side; no plates on the belly; the intestines, spirally con- 

 voluted, are as slender as thread, and twelve or fifteen times longer 

 than the body. From the rivers of South America. (2) 



LoRicARiA, Lacep. 



A single dorsal, forward; edges of the labial veil furnished with 

 several cirri, and occasionally bristled with villosities; under part 



(1) Silurus aspredo, L.; Platystacus lasvis, Bl., Seb. Ill, xx'ix, 9 and 10; — Platys. 

 coiylephorus, Bl., 372; — Silurus hexadadylus, Lac. ,V, p. 82. — The Flatystacus 

 verrucosus, Bl. 373, 3, differs from the other.s in having a shorter anal and tail. 



(2) Loricariapkcostomus, L., B., 374; — Hyp. etentaculum, Spix, IV. 



