404 Mr. McClelland on Isinglass in Polynemus sele. 



Bombay are points at which observations might be made. This ques- 

 may be so easily ascertained, that it is hardly worth forming a con- 

 jecture about it; but if any of the species common to the coasts of the 

 Eastern seas possessed so valuable a property, the chances are that 

 it would have been long since discovered. It is therefore probable 

 that the large gelatine sound will be found to be peculiar to Pol. sele, 

 and perhaps Pol. teria,* Buch. both of which seem to resort chiefly 

 to the Gangetic estuaries at certain seasons, particularly during the 

 North-east monsoon, when it is easy to imagine that the shelter af- 

 forded in those estuaries at that season, might account for many 

 peculiarities which their ichthyology appears to present, compared 

 with that of open coasts. It is during the cold season that the two 

 gigantic fishes above mentioned appear to be caught in most abun- 

 dance, a circumstance the more favourable to any improved opera- 

 tions that might be resorted to with a view to convert them to useful 

 purposes. Whether both contain the same valuable substance, I am 

 unable to say, having as yet only examined P. sele. 



Gen.— POLYNEMUS. 



Two fins on the back, with long filaments attached to the sides in 

 front of the pectoral fins. Opercula covered with scales ; preoper- 

 culum serrated behind. Example. The common Mango-fish of 

 Bengal. 



Yielding Isinglass. 

 P. Sele, Buch. Plate— 

 Sele, or Sulea of the Bengalese. 

 Five filaments, the first reaching from the front of the pectorals 

 to midway between those fins and the anal, the other filaments pro- 

 gressively shorter ; no streaks on the sides, lateral line deflected on 

 the lower lobe of the caudal fin. The fin rays are as follows : — first 

 dorsal seven, second dorsal fourteen, pectorals thirteen in each, 

 ventrals each six, anal twelve or thirteen, caudal twenty (?) The 

 teeth are very fine, continuous below round the edges of the jaws, 

 but interrupted at the anterior part of the upper jaw, behind which 

 a small detached group of palatine teeth are placed on the vomer. 



The liver consists of an elongated left lobe and a short right one, 

 under which the gall bladder is situated. The stomach is a short 

 muscular cul-de-sac, both orifices of which being placed at the an- 

 terior extremity, from which numerous small caca are given off, the 

 intestine extends straight to the vent; in all these respects it corre- 

 sponds nearly with P,paradiseus. The air vessel, which is quite absent 



* P. quadrifilis, Cuv. P. tetradaclylus, &c. and probably refer to the same. 



