270 REPTILES. 



year in fresh-water lakes, which it abandons in the spring to enter rivers. Its colour is 

 dark olive, yellowish and silvery beneath. 



A third species is 



' The Lampern, or Small River-Lamprey, about eight or ten inches in length ; it 

 also inhabits fresh waters, and is distinguished from the former by its dorsal crests, 

 which are continuous or united instead of being distinct. 



The Hag-Fishes (Myxine)* have the mouth armed above by a single 

 fang-like tooth, while the tongue is furnished on each side with two horny 

 plates deeply serrated, so that at first sight they might be supposed to be lateral 

 jaws, like those of articulated animals. In other respects the organization of 



FIG. 293. MYXIXE. 



the hag-fish resembles that of lampreys. Their body is cylindrical, and fur- 

 nished posteriorly with a crest that surrounds the tail ; their mouth is Circular, 

 surrounded by eight cirrhi, and its upper margin is pierced by a spiracle. They 

 have no vestiges of eyes, and their body is lubricated with a great quantity of 

 mucus. Thus provided, the Myxine, when it attacks its prey, uses its mouth 

 like a cupping-glass plunging its fang into the flesh of its victim, and thus 

 securing a firm hold : the lingual saws tear their way into its very vitals. 



The Ammocsetes, f the lowest of the Myxines, have a completely soft and 

 membranous skeleton. They keep in the mud of small streams, and exhibit 

 many of the habits of worms, which they also resemble in their shape. 



CHAPTER XXIV. 

 SECOND CLASS OF VERTEBRATE ANIMALS. 



REPTILES.! 



i- 



THE word Reptile simply means that the animals so desig- 

 nated creep or crawl upon the ground, and, in a general 

 sense, is sufficiently applicable to the class that next offers itself 

 to our contemplation. In some, their unwieldy body, scarcely 

 supported by their short and stunted limbs, presents an uncouth 

 and hideous appearance ; whilst others, furnished with no limbs 

 at all, progress with serpentine movement along the surface of the 

 ground. These animals have ever been looked upon by mankind 

 with involuntary abhorrence, and, by all nations, either despised 

 for their stupidity or dreaded for their malignity. 



* fivt-tvos, myxinos, slime-fish. t Uytt/zoj, ammos, sand ; x^' 7 " 7 ?* chaite, horse-hair. 



+ Repto, to creep or craivl. 



