B. Till.] THE HISTORY OF ANIMALS. 217 



5. Among marine creatures the carabi and astaci cast 

 their skins either in spring or autumn, after having depo- 

 sited their ova ; and carabi have been sometimes taken with 

 a soft thorax, because their shell was ruptured, while the 

 lower part, which was not ruptured, was hard. For the 

 process is not the same in them as in serpents. The carabi 

 remain in concealment for about five months. The crabs 

 also cast their old skin, certainly those which have soft 

 shells ; and they say that those which have hard shells do 

 the same, as the maia and graus. When they have cast 

 their shells, the new shells are first of all soft, and the 

 crabs are unable to walk. They do not cast their skins 

 once only, but frequently. I have now described when and 

 how animals conceal themselves, and what creatures cast 

 their skin, and when they do so. 



CHAPTER XX. 



1. ANIMALS are not all in good health at the same season, 

 nor in the same degrees of heat and cold. Their health and 

 diseases are different at different seasons in various classes, 

 and on the whole are not alike in all. Dry weather agrees 

 with birds, both in respect of their general health and the 

 rearing of their young, and especially with pigeons ; and wet 

 weather, with few exceptions, agrees with fish. On the con- 

 trary, showery weather generally disagrees with birds, and 

 dry weather with fish ; for, on the whole, abundance of drink 

 does not agree with birds. 



2. For the birds with crooked claws, generally speaking, 

 as it was before remarked, do not drink. But Hesiod was 

 ignorant of this circumstance ; for in relating the siege 

 of Nineveh he represents the presiding eagle of the' augury 

 drinking. Other birds drink, but not much ; neither do any 

 other oviparous animals with spongy lungs. The sickness 

 of birds is manifest in their plumage ; for it is uneven, and 

 has not the same smoothness as when they are well. 



3. The generality of fish, as it was observed, thrive the 

 most in rainy years ; for not only in such seasons do they 

 obtain a greater supply of food, but the wet weather agrees 

 with them as with the plants that grow on land ; for 

 potherbs, even if watered, do not grow so well as in wet 

 weather. The same is the case with the reeds that grow IB 



