NOTES ON THE FRESH-WATER FISHES OF INDIA. 433 
Of the migratory fishes of the plains many forms of Carp may 
be observed, more particularly where impassable weirs exist: here 
they may be seen attempting to jump over the obstruction; and 
so common is this occurrence that the natives of India hang 
baskets, cloths, even native cots turned upside down, or anything 
equally suitable, over the sides of the weirs, and into this the 
fish fall. 
In Asiatic waters both monogamous and polygamous forms 
exist, while other phenomena as to breeding deserve attention. 
The walking or snake-headed fishes, Ophiocephalide, of India, 
and other amphibious genera, are perhaps the best known of 
monogamous fishes; some of them reside in ponds, others prefer 
rivers, where they take up their residence in deserted holes which 
they find in the banks. The pond species delight in lying at the 
grassy margins where the water is not sufficiently deep to cover 
them; and here they are able to respire atmospheric air direct. 
The Striped Walking-fish constructs a nest with its tail among 
the vegetation, and bites off the ends of the water-weeds; here 
the ova are deposited, the male keeping guard; but should he be 
killed or captured the vacant post is filled by his partner. The 
Hissar, Callichthys, of South America, is hikewise monogamous, 
constructing a nest, which is also defended. The majority of fishes 
are unquestionably polygamous, as has been repeatedly observed, 
perhaps as distinctly in the case of the Salmon as any other 
species in a wild state, as well as Sticklebacks resident in aquaria ; 
while doubtless fishes which migrate in shoals for breeding pur- 
poses, as the Mackarel, Herring, and some forms of Carp, are all 
polygamous. Warington considered that when the Stickleback 
had propagated its species it died; and Collet has given us an 
~ account of how some globoid fishes, Latrunculus pellucidus, spawn 
in August, and when this has been accomplished they disappear, 
becoming, as he supposes, extinct—being, in fact, annuals among 
animals. 
The time of year at which spawning is effected varies with the 
locality and the family of fish, and depends also on the tem- 
perature of the water and other local causes, while there are some 
fishes which only breed once a year, others more frequently. 
Some fishes do not appear to feed during the season of depositing 
their spawn, as the Salmon, the Shad, and the siluroid Ariine. 
In this country the Twaite Shad leaves the sea at the end of May 
3K 
