INDIAN FISH AND FISHING. 35 



Burmah generally when the June monsoon commences, but 

 not always at the same period, such apparently at times 

 being dependent upon the rapidity of the current and other 

 causes. That it is not solely due to the presence of rain- 

 water flooding the river is evident, because those of the 

 Indus and Irrawaddi are mainly caused by melting snows 

 at this period, and likewise in the latter river these fishes 

 push on to Upper Burmah, to which country the monsoon 

 scarcely extends, but where the inundations are due to 

 snow floods. Probably the cause of the majority of fishes 

 at these various periods ascending the different rivers to 

 spawn may be due to their having been bred there, while 

 inherited instinct causes them to select the most suitable 

 times, when the shallows are covered with water, and ascent 

 is rendered practicable. 



It is evident that members of the same family, genus, or 

 even species, may spawn at very different periods, due to 

 local or climatic causes. There are also fishes which deposit 

 their ova twice yearly, if not more frequently ; these are 

 generally fresh-water forms, and not rare, especially in tropical 

 countries ; as an example, we have the walking-fishes. 



Whether spawning exercises any deleterious effect upon 

 the parent fishes, two replies may be given, as in some 

 cases it renders their flesh unwholesome, while in others it 

 does not cause their character as to food to be much 

 altered. The shad in the East are excellent eating up to 

 the period when they have deposited their eggs, subsequent 

 to which they become thin, flabby, and positively unwhole- 

 some. Fresh-water fishes that deposit a smaller number of 

 eggs, or perhaps do so more gradually, or twice at least 

 during the year, do not invariably appear to be so dele- 

 teriously affected by breeding. 



The size of the eggs, their colour, and whether deposited 



D 2 



