2 SYMBRANCHIATE AND APODAL FISHES 
present or absent. Supraoccipital separated from the 
frontals by the parietals. Shoulder-girdle typically con- 
nected with the cranium; no mesocoracoid. Vertebre 
numerous, the anterior not modified. Ribs present. No 
air-bladder, nor pyloric coca. Ovaries with oviducts 
(cvv, together ; Bpdyxea, gills: in allusion to the confluence 
of the gill-openings). 
Fresh and brackish waters of India and Burmah, 
ranging northward to Korea and Japan, and eastward 
through the Malay Archipelago to Australia and Tasmania ; 
one species from intertropical America. Four families, one 
of them exclusively marine. 
The SymBraNncuiA form a small order of eel-like fishes 
of widely diversified structure inter se. They have been 
separated by the late Professor Cope into two suborders, 
which, with certain necessary modifications originally 
pointed out by Dr. Gill, are here adopted. Jordan and 
Evermann (Fishes of North and Middle America, part 1, 
p. 342) remark of them :—‘‘ They are probably related to 
the Apodes, but this is not certain, and in the structure of 
the head they approach more nearly to the true fishes. 
They rep-esent degraded rather than primitive types, 
and the line of their descent is as yet unknown. It is not 
even certain that the forms grouped in this order are closely 
related.’’? From this it will, therefore, be readily under- 
stood that the members of this order form a peculiarly 
interesting and instructive group. Three out of the four 
symbranchoid families have now been shown to inhabit 
Australian waters, while the inclusion of the fourth is 
probably a mere matter of time. 
The principal differences between the Symbranchia 
and the Apodes are given below in parallel columns :— 
SYMBRANCHIA APODES. 
Premaxillaries present, forming the Premaxillaries absent or atrophied, 
lateral dentigerous border of the the maxillaries forming the 
upper jaw; the maxillaries dis- lateral dentigerous border of 
tinct, lying along their inner edge. the upper jaw. 
Gill-openings confluent across the Gill-openings separate, lateral 
throat. (except in the Synaphobran- 
chide). 
Shoulder-girdle typically connected Shoulder-girdle not connected with 
with the cranium. the cranium. 
