PISCES THORACICI. CH^ETODON. 
61 
CHAETODON. 
GENERIC CHARACTER. 
Caput parvum; os exiguum, labiis retrac- 
tilibus; dentes fplurimisj setacei,jlexiles, 
mobiles , aquales, confertissimi, numero- 
sissimi. Membrana branchialis iii.—vi. 
Corpus latum , tenue, compressum, squamis 
duris vestitum, pidum. Pinna dorsi ani~ 
que rigida, carnosa , squamosa, ut pluri- 
mum aculeis auda. 
The head small, mouth narrow, with re¬ 
tractile lips; the teeth (in many) seta¬ 
ceous, flexible, moveable, equal, very 
numerous and close. The branchial 
membrane iii.—vi. rays. 
Thebody broad, thin, compressed, covered 
with hard scales, and coloured. The 
dorsal and anal fins rigid, fleshy, squa¬ 
mous, and generally with the addition 
of spines. 
No. LXXVIII. 
Ch^etodon cauda panm produdiore in medio; spinis dorsalibus undecem; corpore et pinnis 
maculatis. 
The CrmrroDON with a tail projecting a little at the middle ; the body and fins speckled. 
Chcetodon Argus, Linn. S. JV. p. 46 4. 
Called by the Natives Pool Chitsilloo. 
ii i _4_ 
B. iv. JD. 27. P. 16. V. 6. A. 18. C. 16. 
The body of an irregular roundish form, much compressed, squamous, rough; scales small, orbicular, sub- 
ciliate, tenacious, and (as frequent in this genus) they cover part of the fins. 
The head small, much compressed, declivous, the crown and front only covered with scales. Mouth very 
small, terminal, horizontal; lips thin. The jaws of equal length, extractile. Teeth setaceous, numerous, close, 
equal. Tongue short, roundish, smooth, hardly moveable. Palate smooth. The eyes rather small, distant 
from the rostrum, high, separated from each other by a bony knob, the iris golden. Nostrils double, between 
the orbit and rostrum, one before the other, the anterior round, the posterior oval. 
The opercula smooth, without scales, acuminate. The branchial membrane partly concealed; the aperture 
lateral, large. 
The trunk. The back assurgent, carinate, the breast and abdomen slightly rounded; the sides and tail 
much compressed. The lateral line rising from the upper edge of the opercula, forms an arch ending at the 
narrow part of the tail, whence it is continued straight along the middle of the tail to the fin. The anus 
equidistant from the head and caudal fin. 
The fins. The dorsal long, compound, interrupted; the first part possesses the straight ridge of the back, 
consisting of eleven spinous rays, lodged in a groove, into which they occasionally recline: the second part 
