( 29 ) 



practical question is, whether, when food and water fails, 

 some fish do not aestivate until the return of a more 

 favourable season. Natives of India assert that they do thus 

 become torpid in the mud. As the water in tanks becomes 

 low, the fishes congregate together in holes and places in 

 which some still remains, where they may be frequently seen in 

 numbers, huddled together with only sufficient water to cover 

 their dorsal fins. If disturbed, they dive down into the thick 

 mud, so that a net is often found ineffectual to take them. 

 The plan employed to capture them is for the fisherman to 

 leave the net in the water, and to walk about in the surround- 

 ing thick mud ; in time they come to the surface to breathe, 

 and fall an easy prey. As the water gradually evaporates, 

 the fishes become more and more sluggish, and finally, there is 

 every reason to believe that some at least bury themselves in 

 the soft mud, and in a state of torpidity await the return of the 

 yearly rains. In Ceylon, Mr, Whiting, the Chief Officer 

 of the western province, informed Sir Emerson Tennent 

 that he had accidentally been twice present when the villagers 

 had been engaged in digging up fish. The ground was firm 

 and hard, and " as the men flung out lumps of it with a spade, 

 they fell to pieces, disclosing fish from nine to twelve inches 

 long, which were full-grown and healthy, and jumped on the 

 bank when exposed to light." Many other animals which 

 possess a higher vitality than fish aestivate during the hot 

 -months, as Batoachians, the Emys, the Lepidosiren anneclens, 

 and some of the Crocodiles. Molluscs and land-snails 

 are commonly found in this state during the hot and dry 

 seasons. 



Migrations of Fish. 



XLV. The subject of the migrations of fish during 

 „ , , the periods of rain is of great practical 



Mi-rations of tisb. x ..,. j_i /*» i 



importance, it being mostly eriected 

 for the purpose of breeding, but in some few instances 

 is due to predaceous fishes being in pursuit of their weaker 

 neighbours. At the commencement of the rains fish be- 

 come very excited and disturbed ; apparently unsatisfied 

 with the localities they inhabit, they restlessly seek a 

 change to other pieces of water. This may be owing to the 

 same instinct which causes the migration of marine fish 

 to the fresh-water, or the necessity of obtaining a suitable 

 place in which to deposit their ova. It is generally at this 

 season that some have been observed travelling on land, and 

 it has been imagined that places which are only occasionally 



