324 
acting pter ran. 
Family SILURIDiK. 
Supraoccipital bone prominent ; otic region completely 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 bordci 
of the mouth : teeth very variable ; lower pharyngeals rarely talc> 
form and conspicuously toothed. Barbels present. Suboperculum 
usually absent, and branchiostegal rays few or wanting. Pectora 
aich without distinct suj)raclavicle ; a single dorsal fin often follow 1 
b) an adipose dorsal on tho tail. Trunk without scales, but ot'n 11 
more or less armoured with bony' scutes. 
The existing members of this family are distributed in the itesh 
" aters of all temperate and tropical regions, and a few are littora 
marine species. No extinct genera of importance are known. 
figures of the skeleton of Synodontis are given by C. B. Briib ^ 
Zootomie aller Thierclasscn (1884), pis. cxxxi., cxxxii. T e 
weberian ossicles are described by Haddon and Bridge, Phil. Trans- 
1 sy 3 B, pp. (>5-333, pi 8 . 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 su P ra 
occipital and frontal bones. Eyes small ; cloft of mouth transverse, 
terminal, of moderate width; teeth on dentary, premaxilla, an 
vomer. Pectoral fins with robust spine, often serrated on t 
anterior border ; pelvic fins with six rays : dorsal fin without s P lD > 
much extended and occupying nearly the whole of tho back • a 
adipose dorsal ; anal fin much extended : caudal fin rounded. > 
naked. 
This gcuus survives in the froshwaters of Africa, the East Indie , 
and the intermediate portion of Asia. 
Clarias falconer!, Lydekker. 
188C. Clarias falconeri, 1!. Lydekker, Pa'aeont. Indica, ser. x, 
p. 217, pi. xxxvii. fig. 1. 
Type. ’Middle portion of skull : British Museum. 
A species probably about 0-45 in length, known only by the ml 
portion of the skulli Rugose ornament of cranial roof rather 
