120 CLASS XIV. 



Animal Economy, 1837, pp. 415 421, PI. 56,57; G. VALENTIN, Beiiraye 

 zur Anatomic des Zitteraales, Neuchatel, 1841, 4to, (A us dem viiten Bde 

 der Neuen Denkschriften der allg. Schweizer. Gesellsch. f. Naturwissenschaf- 

 ten,) and in WAGNEE'S HandworterbucJi der Physiol. i. s. 266, 273. 



See also, especially on the mode of capture of Gymnotus to which we have 

 alluded, HUMBOLDT in his Recueil d'Observat. de Zool. et d'Anat. comp. i. 

 pp, 83 148, Reise in die ^Equinoctial Gegenden, m. s. 294 324. Physical 

 and chemical experiments with Gymnotus were performed especially by 

 FARADAY some years ago; Philos. Transact, for 1839, Part i. p. i, and 

 following. 



Family XXIII. Symbranchii. Pectoral belt annexed behind 

 the head to the spinal column. Upper margin of mouth formed 

 by intermaxillary bones descending to the angle of mouth, the 

 supramaxillaries being placed next to them. Teeth in jaws and 

 bones of palate. Branchial aperture single under the throat. 

 Ovaries supplied with duct. Intestinal tract straight, and without 

 pyloric appendages. Swimming-bladder none, at least in most. 



Monopterus COMMERSON. Common branchial aperture trans- 

 verse, divided by a septum. Teeth very small, subulate, crowded 

 in jaws and palate. Lips fleshy, expanded beyond the margin of 

 jaw. Pectoral fins none. Dorsal and anal fins remote, confluent at 

 the apex of tail. (Branchiostegous membrane with six rays; only 

 three pairs of branchiae.) Posterior orifice of nostrils above the 

 eye, anterior below the eye. 



Sp. Monopterus javanensis COMMERS., LACEP. The Rijk's Museum possesses 

 specimens of this genus from Java and Borneo, up to 2' feet in length. 



Amphipnous MUELL. Common branchial aperture divided by a 

 septum. Head narrowed in front of eyes, obtuse at the apex. 

 Posterior aperture of nostrils above the eyes, anterior at apex of 

 snout. First and fourth branchial arch without branchiae. Two 

 small bladders, respiratory, open into the mouth in front of first 

 branchial arch. Body finless; tail compressed, with a sharp edge 

 above and below, acuminate. 



Sp. Amphipnous cuchia, Unibranchaperlura cuchia, BUCHANAN Fishes of the 

 Ganges, PL 16, fig. 4, pp. 16, 17. The respiratory sacs receive blood from 

 the branchial arteries of the second and third branchial arch, and send 

 their veins to the aorta ; two of the arches of the branchial arteries go 

 immediately into the aorta. TAYLOR in Edirib. Journal of Science, v. 1831, 

 pp. 4249. 



