THE 
WANDERING SILURUS. 
Generic Character. 
Head naked, large, deprefled. 
■Mouth wide, generally furnifhed with long ten- 
tacula or beards. 
Firft ray of the pectoral and dorfal fins commonly 
firong and ferrated backwards. 
Specific Character, &c. 
SILURUS with a double range of fcales, four 
beards, and the laft dorfal fin fingle-rayed. 
Gron. mtif. 3. t. 29. fig. 13. 
Marcgr. bras. 151. 
The beautiful and varied ftrudture which diftinguilhes 
the fcales of fifhes, has long afforded an extenfive field 
for microfcopical obfervation. In fome the fcales are 
of an oval fhape, with concentric rings of reticulated 
fibres; in others of a fquarifh form, with the fibres 
curioufly difpofed into difiimilar patches or fubdivifions, 
and ornamented at the extremities with a feries of trans¬ 
parent aculei or prickles. In fome filhes the fcales are 
fo extremely fmall as to be fcarce diftinguifhable on a 
curfory view, and in fome they are not only very fmall, 
but 
