STJEURACHIAN MALACOPTi:UVGIANS. 217 



AcHiRUs, Lacep. 



Soles totally deprived of pectoral fins. 



They may also be divided into Aciimus properly so called*, in which 

 the vertical fins are distinct; and into Plagusia, Brownt, in which they 

 are united with the caudal. 



The third family, which wc shall call, 



FAMILY III. 



DISCOBOLI, 



On account of the disk formed by their ventrals, comprehend two small 

 genera. 



Lkpadogaster, Gouan. 



They are small fishes, remarkable for the following characters: their 

 ample pectorals, having reached the inferior surface of the trunk, assume 

 stouter rays, curve slightly forwards, and unite with each other on the 

 throat by a transverse membrane directed forwards, which is formed by 

 the union of the ventrals. The body is smooth and without scales, the 

 head broad and depressed, the snout salient and protractile; the branchias, 

 but slightly cleft, are furnished with four or five rays, and they have but 

 a single soft dorsal opposite to a similar anal. The intestine is short, 

 straight, and without casca, and notwithstanding they are deprived of a 

 natatory bladder, they may be seen swimming along the shores with great 

 vivacity. In 



Lepadogaster, properly so called, 



The membrane which represents the ventrals extends circularly under 

 the pelvis, and forms a concave disk ; on the other side the bones of the 

 shoulder project slightly behind, which completes a second disk by means 

 of the membrane which unites the pectorals. Several species inhabit the 

 seas of Europe. 



In some, the dorsal and anal are separated from the caudal, with which, 

 however, their membrane is sometimes continuous, but becomes nar- 

 rower :J:. 



In others, the three fins are united §. In the 



* PLachirus,L.,Jchire barbu, Geoff. Ann. d\i Mus. vol. I, pi. xi. It is not the same 

 as that of Lacep. It is necessary to observe that its barbs are not rays, but cilia, 

 such as are found in the common Sole, and on many of the Achiri; — the jicli. mar- 

 hre, Lac. Ill, xii, 3, and IV, p. 660; — the Ach.fasce, Id., PI. lineatus, Sloane, Jam., 

 pi. 346;— P/. mollis, Mitch. II, 4. 



t PI. bilineafus, Bl. ISS, or Jerie potoo, E, Russel, 74; — the Ach. onie, Lacep. IV, 

 p. f!63; — Pleur.arel, Sch. 15!>, PI. plaguiia", aff., Jam., Br. 445, diflerent from the 

 PL plagiusa, L. ; — PI. potoiis, Cuv., or Jerre potoo, D, Russel, 73. 



X Lepadog. gouaii, Lacep. I, xxiii, 3, 4, or Lep. rvstratus, Schn.;-—Lep. balbis, Risso, 

 pi. iv, f. 9, probably the same as the Cyclopt. coriiubkus, Sh., Cornish Sucker, or 

 Ji^ra sucker, Penn. Brit ZooL, No. 59;— Lep. Decandolle, Risso, p. 76. 



§ LepadogHster Wildcnow, Risso, p. 76. 



