402 coxTiiinunoNS TO NORTH AMERICAN ICHTHYOLOGY iv. 



anal spines .">, rapidly iLjTaduated ; ventral (ins abdominal, not far bade, 

 attached to the elongate coracoid bone, composed of one spine and live 

 rays; caudal forked. Air bladder lar.u'e, simple. Inlestinal canal Ion-'. 

 Peritoneum usii illy black. Vertebra- 1*4. (ienera ." ; species 70-80; 

 inhabiting the fresh waters and coasts of warm regions, feeding on 

 organic mat ter contained in innd. A considerable indigestible portion of 

 the latter is swallowed, and in order to prevent larger bodies from pass- 

 ing into the stomach, or substances from pissing through the .uill-open- 

 in.U's, these fishes have the organs of the pharynx modified into a 

 filtering ap])aratns. They take in a quantity of sand or mud. and 

 after having worked it for some time between the pharvuyeal bones, 

 they eject the roughest and indigestible portion of it. The upper 

 pharyn.u'e.ds have a rather irregular form ; they are slightly arched, the, 

 convexity being directed towards the pharyn.ueal cavity, tapering an- 

 teriorly, and broad posteriorly. They are coated with a thick, soft 

 membrane, which reaches far beyond the margin of the bone, and is 

 studded all over with minute horny cilia. Each branchial arch is pro- 

 vided with a series of long gill-rakers, which are laterally bent down- 

 wards, each series closely fitting to the sides of the adjoining arch; 

 they constitute together a sieve admirably adapted to permit a transit ' 

 for the water, returning at the same time every solid substance in the 

 cavity of the pharynx, (dihithcr.) 



The Miii/iliilif, A(ln'rinitl<v, tfjtlti/rti'Hi'lo', and OpMocephdlidCB compose 

 the group or suborder of /V/vr.vmv.v, thus eharacteri/ed. Ventral fins 

 abdominal; branchial arches well developed, the bones all present ex- 

 cept t he fourth superior branchihyal. Third superior phar\ lineal much 

 enlar-cd ; hwer ]>hai'y lineal distinct. Scales cycloid. .Pectorals ele- 

 vated, about on a level with the upper posterior an.ule of operciilnin; 

 spinous dorsal usually present. (Latin, 7Vm(, a perch; fco.r, a pike 

 the -TO up bein- intermediate in its position between the Percoids and 

 the lld/ilu/ni.) 



(Mn>lili,l,i- (iiintli.T, iii. in'.". 



*.l:i\vs \\itli :i vi-rii-s (if cili.-i. l>ut \vitliunt true trrtli; ]>:irt <>l' tin- stuinncli inusciilar, 



1U5. 



195. 



(MuUets.} 



(Arti-.li: Linniriis, Byst. \:il.: t \ ]" Mmjll < i>lialun I>.) 



I'.ody oblong, somewhat compressed, covered with larijo cycloid scales. 

 Head large, bluntish, convex above, scaled. Mouth small. Jaws tooth- 





