MALACOPTEKYGIT SUBRACHIATI. 253 



AcHiRus, Lacep. 



Soles totally deprived of pectorals. 



They may also be divided into Achirus properly so called, (l) in 

 which the vertical fins are distinct; and into Plagusia, Brown, (2) in 

 which they are united with the caudal. 



FAMILY III. 



DISCOBOLI. 



These fishes, so called on account of the disk formed by 

 i their ventrals, form two genera. 



Ul Lepadogaster, Gouan. 



The small fishes which compose this genus are 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 caeca, and notwithstanding they are de- 

 prived 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 



(1) PI. achirus, I.., Mare barbu, Geoff., Ann. du Mas., vol. I, pi. xi. It is not 

 the same as tliat 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 

 ^ck. marbre, Lac, III, xii, 3, and IV, p. 660; the dch. fasc^, Id., Fl. lineatus, 

 Sloane, Jam., pi. 346; PL mollis, Mitch., II, 4. 



(2) PL bilineatus, lil, 188, or Jerre potoo, E, llussel, 74; the ch. orne, Lacep., 

 IV, p, 663; Plcur. arel, Sch., 159, PL plagusix, aff., Jam., Br. 445, different 

 from the PL plagiusa, L. ; PL potous, Cuv., or JerrS potoo, D, Russel, 73, 



