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In the Haidarabad Assigned Districts, the Tehsildar of 

 Buldana (para. 238) observes that "disturbing the water 

 of a stream, so as to cause it to become muddy, is said some- 

 times to cause the fish to die." Also in Oudh, the Commis- 

 sioner of Faizabad (para. 276) reports fish being taken 

 in village ponds and jhils, in the months of Jeth and 

 Baisakh, by hand, the water being first mudded by gangs 

 of from 50 to 60 men. This sudden fouling with mud, 

 causing death to water-breathing fishes, is likewise observed 

 during the monsoon months, where a sudden descent of very 

 muddy water suffocates this class of fishes. The Collec- 

 tor of Tanna (para. 101) remarks that, when the rivers 

 become muddy at the commencement of the monsoon, 

 fish die in large numbers, also when they become 

 nearly dry at the close of the hot weather. Also (para. 

 187) "in Sittimungalum, it is observed of the Bhowany 

 Biver that fish die when the water is mixed with mud to a 

 large extent, as during the monsoons ; this has also been 

 observed in Malabar. Secondly, some species, which, although 

 they to a limited extent are " water-breathers," are more 

 essentially " air-breathers," having a compound respiration, 

 consequently muddy water hardly affects them. Thus, in 

 carrying live specimens of Ophiocephalus from the plains to 

 the Nilghiri hills, this was most successfully accomplished in 

 water largely mixed with mud. They never obtain oxygen 

 for any length of time from the air in solution in the sur- 

 rounding water, but inspire it direct from the atmosphere, no 

 matter how cool and charged with air the water may be ; and 

 if unable to inhale atmospheric air, become poisoned by 

 the carbon remaining in their circulation. The compound- 

 breathers expire in a longer or shorter interval if un- 

 able to reach the atmospheric air ; amongst these are the 

 climbing perch, An abas scandens, and the species of the 

 Acanthopterygian genera, Poly acanthus, Trichogaster, and 

 Ophiocephalus, all of which possess a cavity above the gills 

 for the purpose of the reception of air for respiratory require- 

 ments. The difference between the respiration of the " water- 

 breathers" and the "compound-breathers," as defined, 

 is very apparent when they are lying side by side at the 

 bottom of an aquarium. Thus, the Macrones carcio has its 

 gills in constant excited movement, whilst the Ophiocephalldce 

 scarcely move theirs, but at intervals rise to the surface, 

 open their mouths, and take in air. This latter phenomenon 

 f breathing the air pure, and not subsequent to its solution 



