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Family SILURID.^. 
^''‘^2c.4y^ 
'<;/^^ CaU^ <3* .gy^- 
SupraocciiDital bone prominent; otic region com 2 )letely roofed by 
membrane-bones ; brain-case produced forwards between the orbits : 
cheek-plates much reduced. Symplectic bone absent; premaxilla 
extended, almost always excluding the maxilla from the upper border 
of the mouth ; teeth very variable ; lower pharyngeals rarely falci¬ 
form and conspicuously toothed. Barbels present. Suboperculum 
usually absent, and branchiostegal rays few or wanting. Pectoral 
arch without distinct supraclavicle : a single dorsal fin often followed 
by an adipose dorsal on the tail. Trunk without scales, but often 
more or less armoured with bonv scutes. 
The existing members of this family are distributed in the fresh- 
waters of all temperate and tropical regions, and a few are littoral 
marine species. Xo extinct genera of importance are known. 
Figures of the skeleton of Synodontis are given by C. B. Briihl, 
Zootomie aller Thierclassen (1884), pis. cxxxi., cxxxii. The 
weberian ossicles are described by Haddon and Bridge, Phil. Trans, 
1893 B, pp. 65-333, pis. xi.-xix. 
Genus CLARIAS^ Gronow. 
[Zoophyl. Gronov. 1781, p. 100.] 
Head depressed and bones of cranial roof ornamented and exposed, 
or covered only with very thin skin ; a small vacuity in the supra- 
occipital and frontal bones. Eyes small; cleft of mouth transverse, 
terminal, of moderate width; teeth on dentary, premaxilla, and 
vomer. Pectoral fins with robust spine, often serrated on the 
anterior border ; pelvic fins with six rays; dorsal fin without spine, 
much extended and occupying nearly the whole of the back ; no 
adipose dorsal: anal fin much extended; caudal fin rounded. Skin 
naked. 
This genus survives in the freshwaters of x\frica, the East Indies, 
and the intermediate portion of Asia. 
Clarias falconeri, Lydekker. 
1886. Clarias falconeri, E. Lydekker, Pa^£eont. Iiidica, ser. x, vol. iii, 
p. 247. pi. xxxvii. fig. 1. 
Type. Middle portion of skull: British Museum. 
A species probably about 0*45 in length, known only by the middle 
portion of the skull. Eugose ornament of cranial roof rather fine, 
