CHAPTER X 
THE SCYPHOPHORI, HAPLOMI, AND XENOMI 
%)| RDER Scyphophori.— The Scyphophori (oxvdos, cup; 
i popéew, to bear) constitutes a small order which lies 
&| apparently between the Gymnonoti and the Isospondylz. 
Boulenger unites it with the Isospondyli, The species, about 
seventy-five in number, inhabit the rivers of Africa, where 
they are important as food-fishes. In all there is a deep 
cavity on each side of the cranium covered by a thin bony 
plate, the supertemporal bone. There is no symplectic bone, 
and the subopercle is very small or concealed. The gill-openings 
are narrow and there are no pharyngeal teeth. The air-bladder 
connects with the ear, but not apparently in the same way as 
with, the Ostartophysan fishes, to which, however, the Scypho- 
phori are most nearly related. In all the Scyphophori the body 
is oblong, covered with cycloid scales, the head is naked, there 
are no barbels, and the small mouth is at the end of a long 
snout. All the species possess a peculiar organ on the tail, 
which with reference to a similar structure in Torpedo and 
Electrophorus is held to be a degenerate electric organ. Accord- 
ing to Gunther, “it is without electric functions, but evidently 
representing a transitional condition from muscular substance 
to an electric organ. It is an oblong capsule divided into 
numerous compartments by vertical transverse septa and con- 
taining a gelatinous substance.” 
The Mormyride.— There are two families of Scyphophori. 
The Mormyride have the ordinary fins and tail of fishes and the 
Gymnarchide are eel-like,.with ventrals, anal and caudal wanting. 
Gymnarchus miloticus of the Nile reaches a length of six feet, 
and it is remarkable as retaining the cellular structure of the 
air-bladder as seen in the garpike and bowfin. It doubtless 
serves as an imperfect lung. 
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