40 MEMOIR OF RONDKLET. 



red, of a bright and beautiful tint, deeper than 

 cinnabar. These parts shine in the night, so that 

 the animal seems to hold burning coals in its 

 mouth, from which it may be supposed to be the 

 fish named lucerna by the ancients. This fish has 

 a very short throat ; its stomach has numerous ap- 

 pendages ; a gall-bladder in the liver, and an angu- 

 lar heart. The ova are red. It flies out of the water 

 that it may not be preyed on by larger fishes, as we 

 are informed by Oppianus and Aristotle. Marine 

 hirundines also make a noise in flying ; and the 

 cause of this is a small and narrow fissure in the 

 branchiae, for the air, on being pressed through a 

 narrow aperture, produces a stridulent noise. For 

 this same reason, the hirundo can live longer in the 

 air, because the latter does not enter suddenly nor 

 abundantly through tlie narrow holes of the bran- 

 chiae, and, having once entered, it is more easily re- 

 tained. The flesh of this fish is hard and dry, 

 affording much nourishment, but it is difiicult of 

 digestion. Owing to the flesh being so hard, it 

 becomes better and more tender by long keeping ; 

 hence it is that it is better when carried to Rome 

 than when used near the shore. I have found that 

 the gall of the hirundo may be used with benefit in 

 cases of suffusion of the eyes. The fish, as we have 

 figured it, resembles the cucullus and mullet, both 

 in colour and form of body; but it has very long and 

 broad wings, and flies out of the water, as many 

 who have seen it assure us. Those who have sailed 

 through the Straits of Gibraltar affirm that they 



