598 LEW EOS PEt CHAP. 
from China, Japan, and the Malay region; and Chilobranchus, 
with two species from Australia and Tasmania. Although the 
South American Symbranchus has been observed to live in 
marshes which periodically dry up, the Fish burying itself in the’ 
mud like a ZLepidosiren, the branchiae are fully developed on 
the four branchial arches. In Monopterus, of similar habits, the 
branchial laminae are rudimentary, and on three arches only. No 
accessory breathing organ is known to exist. 
m ar g : top, sop op * 
pop br bra 
Fic. 361.—Monopterus javanensis. Lower view of head, showing gill-opening (go) : lower 
view of middle praecaudal vertebrae: and side view of skull and pectoral arch. 
ar, Articular; br, branchiostegal rays; bra, branchial arches; c/, clavicle; d, dentary ; 
eot, epiotic; eth, ethmoid; f, frontal; hm, hyomandibular; cop, interoperculum ; 
m, maxilla ; mpt, metapterygoid ; , nasal; op, operculum ; p, parietal ; pm, prae- 
maxilla; pop, praeoperculum ; ppt, pterygopalatine ; ptte, post - temporal ; 
q, quadrate ; scl, supra-clavicle ; so, supra-occipital ; sop, suboperculum ; sq, squa- 
mosal ; sy, symplectic. 
Fam. 2. Amphipnoidae.— Post-temporal absent, the shoulder- 
girdle free from the skull. The Cuchia, Amphipnous cuchia, the 
sole representative of this family, an inhabitant of the fresh and 
brackish waters of India and Burma, growing to two feet in 
length, is remarkable for the presence of a respiratory air-sac 
on each side of the neck behind the head, communicating 
with the gill-cavity. Of the three branchial arches the second 
alone possesses gill-filaments; the third supports, in their place, 
a thick and semi-transparent tissue; the principal organs of 
respiration are two small bladders, resembling the posterior 
portions of the lungs of snakes, which the animal has the power 
