10 O SIREN LACERTIXA. 



SrwoNYMES. Siren lacertina, Linnxus, Amoenit. Acad., torn. vii. p. 311. 

 Mud iguana, Ellis, Phil. Trans. London, vol. lvi. p. 1S9. 

 Murena siren, Gmelin, Syst. Nat. Linn., torn. i. pars iii. p. 1136. 

 Siren lacertina, Shaio, Gen. Zool., vol. iii. p. 601. 

 Siren lacertina, Schneider, Hist. Amphib., fas. i. p. 88. 

 Siren lacertina, Daudin, Hist. Nat. des Rept, torn. viii. p. 272. 

 Siren lacertina, Mcrrem, Versuch eines Syst. der Amphib., p. 1SS. 

 Siren lacertina, Harlan, Med. and Phys. Res., p. SS. 

 Mud Eel or Siren, Vulgo. 



Description. The head is rather small for the size of the animal, sub-oval, 

 with the forehead elevated, and the snout flattened and truncated. The mouth is 

 small, and covered with tolerably thick lips; the tongue is arrow-shaped, broadest 

 and adherent posteriorly, free only at its anterior and lateral margin. There are 

 no teeth in the upper jaw, but a broad group of numerous minute teeth begins at 

 the anterior margin of the palate bones and extends along their outer border. 



The nostrils are small, latero-anterior, and open outwards. The eyes are 

 superior, very small, black, and covered with a cuticular prolongation. The neck 

 is contracted, with three spiracles or branchial openings, elliptical, vertical, the 

 central one largest; these are covered by three branchial tufts, of which the 

 anterior is smallest and the posterior largest. 



The body is eel-shaped, though robust; the tail is long, compressed, ancipital, 

 with a rayless fin both above and beloAV. 



The anterior extremities alone exist, and these are but slightly developed, so as 

 to be of little service, if any, in progression, and yet they are in constant motion 

 as the animal moves from place to place on land, and are folded back when it 

 .swims in water. There are four short fingers to each extremity, the tips of which 

 are rather pointed, slightly curved, and terminate in semicorneous tips. 



Colour. The whole superior surface is dusky, sometimes almost black, and is 



