452 
Genus Amphlpnous Milller 
Amphlpnous MILLER, Abhandl. K. Preuss. Akad. Wiss., 1841, 
P. 246, Type Unibranchapertura cuchla B UCHANAN HAMILTON. 
Pneumabranchus MC CLELLAND, Calcutta Journ. Nat. ^ist., vol. 
5, 1845, p. 175 (192). Type Pneumabranchus striatus 
MC CLELLAND, designated by JORDAN, Genera of Pishes, pt. 
2, 1919, p, 220. 
Palatine teeth uniserial, well developed. Gill membranes 
nearly entirely joined with isthmus; with single transverse 
opening. Branchial arches 3, with gill filaments rudimentary, 
divided by narrow slits. Branchiostegals 6. Respiratory sac 
on neck behind head communicating with gill cavity. Scales 
present, in longitudinal rows. 
