298 piiht's NATTJEAI HISTOUT. [Book VIII. 



on the bants of rivers, just as though with a knife.^ If they 

 seize a man by any part of his body, they will never loose 

 their hold until his bones are broken and crackle under their 

 teeth. The tail is like that of a fish ;^ in the other parts of 

 the body they resemble the otter ;^ they are. both of them 

 aquatic animals, and "both have hair softer than down. 



CHAP. 48. (31.) BBAMBLB-fEOaS. 



Bramble-frogs,^ also, which live both on land and in water, 

 are replete witii various medicinal substances, which they are 

 said to discharge each day, and to take in again with their 

 food, of which they only retain the poisonous parts. 



CHAP. 49. THE SEA-CALF ; BEAVEES ; IIZAEDS. 



The sea-calf, too, lives equally in the sea and on land, 

 being possessed of the same degree of intelligence as the beaver. 

 It vomits forth its gall, which is useful for many purposes in 

 medicine ; also th^ rennet,^' which serves as a remedy in 

 epilepsy ; for it is weU aware that it is bunted for these sub- 



^ The beaver has the most powerful teeth of any animal of the class 

 Rodentia, to which it belongs ; it uses them for cutting down trees, with 

 which it constructs its habitation. Aristotle, Hist. Anim. B, viii. c. 5, 

 refers to this. — B. 



'* The tail is covered with a kind of scale, and is flattened ; but, in its 

 internal organization, is formed like those of other quadrupeds. — B. 



3' See B. xxxii. c. 52. 



'8 Pliny, speaking of the difi'erent kinds of frogs,. B. xixii. c. 18, says, 

 " There are some which live only in the hedges, and thence have the name 

 of rubeta, or bramble frogs." It seems impossible to identify this reptile 

 with any of our known animals : and we may conclude that there is no 

 foundation for the statement, -ffilian gives am account of the venomous 

 nature of this animal. Anira. Nat. B. xvii. c. 12. — B. 



" As Cuvier remarks, it is impossible that any animal can discharge by 

 vomiting what Pliny terms the " coagulum," which is the fourth stomach 

 of a ruminant animal; the same substance which, under the -name of 

 rennet, is employed to coagulate milk. He conjectures, that the error may 

 have originated in the observation, that occasionally in fish, when suddenly 

 drawn out of the water, the air-bladder is protruded fi-om the mouth, 

 which may have been mistaken for the stomach. The circumstance is 

 mentioned by Aristotle, Hist. Anim. B. viii. ci 23, and by .ZBlian, Anim. 

 Nat. B. iii. c. 19, as well as the vomiting of the bile ; respecting this 

 latter, we may remark, that vomiting is produced in various animals, when 

 under the influence of extreme terror. — B. 



