255 
Explanation of Plate I. 
Figs. 1, 2, 4, Head. Natural size. Fig. 6, Tail. Natural size, 
Fig. 3, Head. Magnified. Fig. 7, Vertical section of the body. 
Fig. 5, Dentition. Magnified. Natural size. 
Fan. SIJMBRANCHOÏDAE. 
Gen. Syuarancuus (Bloch- Schneider 1801.), Bleeker 1852. 
(Syn. Unibranchapertura , Lacépède 1803. — Ophisternon , Me 
Clelland 1844. — Tetrabranchus Bleeker 1851. —) 
Dorsal , anal and caudal fins united, adipose; pectorals none. 
Four distinct branchial arches with very conspicuous interve- 
ning apertures. A single branchial aperture, communicating 
with the branchiae of both sides. Branchiostegous membrane 
with six rays. Maxillary-, vomerine-and palatal teeth dis- 
posed in single or more series, vomero-palatals in an archs 
Skin smooth, without scales. Anus situated in the posterior 
third of the body. 
Symbranchus immaculatus Bloch. Tab. IL. 
Synon. Synbranchus immaculatus Bloch, Ausl. Fische Tab. 419, Fig. 
1 (excl. Habit. Surinam). 
Synbranchus immaculatus Bloch-Schneider, Syst. Posth. Tab. 
103, Fig. 1. 
Synbranchus ifamaeculatus Shaw, Gen. Zoöl. IV, p. 36. 
Synbranchus immaculatus Cuvier: Règne Anim. II, p. 354 (2) 
(exel. synon). 
Symbranchus immaeulatus J. Müller, Myxin. in Abh. König]. 
Akad, Berlin 1839, p. 245. 
Ophisternon bengalensis McClelland, Calc. Journ. Nat. Hist. 
V, pp. 197, 220, Tab. II, Figs. 1, 2. (Adult). 
Symbranchus immaculatus Cantor: Catal. Mal. Fish, in Journ. 
As. Soc. Beng. XVII, p. 1919 (Young). 
