ARAPAIMA S. 
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pterotic bone devoid of a cavity in its interior. Externally these fishes may be 
recognised by the naked body and the absence of barbels 5 the fatty fin being 
absent, and the medium-sized dorsal opposite the anal. Internally the air-bladder 
is large and simple; and the eggs, as in the last family, fall into the abdominal 
cavity. Represented by rather more than a dozen species, the largest of which 
seldom exceeds 8 inches in length, these fish are of especial interest from a 
distributional point of view, since they occur in such isolated areas as New 
Zealand, New South Wales, Tasmania, and the southern extremity of South 
America. From their spotted bodies, the New Zealand representatives of the genus 
were formerly known as trout by the colonists. An allied New Zealand genus 
(■ Neochanna ), represented by a single species, differs in the absence of pelvic fins; 
all the known specimens of this singular form having been found buried in burrows 
of clay or hard mud at a considerable distance from the water. 
BRAZILIAN ARAPAI^IA (Jg liat. size). 
The Arapaimas,— Family Osteoglossidje. 
Agreeing with the last family in the conformation of the base of the skull, 
the large tropical fresh-water fishes, which may be collectively known as arapaimas 
(although this name properly belongs only to the Brazilian species here figured), 
