436 
Genus Macrotrema Regan 
Macrotrema REGAN, Ann. Mag, Nat. Hist., ser. 8, vol. 9, 
1912, p. 390. Type Symbranchus callgans CANTOR, mon- 
otypic. 
Body naked, elongate, cylindrical. Tail greatly compress¬ 
ed, short tapers. Eyes vestigial, covered,by skin. Lips well 
developed, lower reverted over lower jaw. Setaceous teeth uni¬ 
serial or premaxillaries, crowded to triangle near symphysis; 
palatal teeth obtusely conic and stronger, uniserial, arched; 
lower jaw teeth still stronger, single series expanded near 
symphysis into semilunar band of 3 or 4 series. Front nostril 
I 
small than hind one, edges raised, near snout tip. Hind nost¬ 
ril lanceolate, opening obliquily above eye. Gill opening 
forms single aperture which very wide and extends up sides to 
lateral line. Four gill arches, all with well developed gills. 
Vertebrae about 100. Lateral line present. Dorsal and anal 
low rayless folds of skin, confluent with small caudal which 
with 10 rays. No paired fins. 
One species in Malaya. Smaller than Synbranchus and marine 
in habit. 
