BO THE PHILOSOPHY 



moved ; becaufe it has been found, that, like other animals, 

 they have a complete organ of hearing, and that water is a 

 proper medium for the conveyance of found. JBefides, in the 

 in the ilcate, and fome other genera, the learned and inge- 

 nious Dr. Monro, ProfeiTor of A.natomy in the College of 

 Edinburgh, has lately difcovered an aperture which leads di- 

 jreflly to the internal parts of the ear. 



The gullet of iiihes is fo fhort that it is hardly to be dif- 

 tinguifhed from the ftomach, w^hich is of an oblong figure. 

 The guts are very fhort, making only three convolutions, the 

 laft of which terminates in the common vent for the faeces, 

 urine, and femen. From this ftructure of the ftomach and 

 inteftines, analogy would lead us to conclude, that fifhes 

 live chiefly upon animal food. Experience, accordingly, 

 teaches us, that almoft all fiflies prey upon the fmaller kinds, 

 and even devour their own young. The liver is proportion- 

 ally large, of a whitiih colour, and iituated on the left fide. 

 The gall-bladder lies at a confiderable diflance from the 

 liver, and difcharges the gall into the gut. In fifhes, the 

 organs of generation are two bags fituated in the abdomen, 

 and uniting near the anus. In the male, thele bags are filled 

 with a thick whitifh fubftance called the ;«///, and in the fe- 

 male with an infinite number of minute eggs called the roe. 

 At the feafon of fpawning, the bags, of both male and fe- 

 male are greatly diftended ; but, at other times, the male 

 Organs can fcarcely be diflinguifhed from thofe of the fe- 

 male. 



The fwimming bladder is an oblong, white, membranous 

 bag, which contains nothing but a quantity of claftic air. 

 It lies clofe to the back-bone, and has a pretty flrong mufcu- 

 lar coat. By contracTdng this coat, and, of courfe, condenf- 

 ing the air it contains, fome fifhes are enabled to render 

 their bodies fpecifically heavier than water, and to fink to 

 the bottom ; and, when the mufcuiar fibres ceafe to adl, the 



