INTRODUCTION. xv 



fish fauna, as out of 69 Genera 35 are CarjJs, 26 Siluroids, and 19 AcantJiopterygians, of whicli last 6 are 

 modified by an amphibious respiration for special tropical requirement ; and of these last forms the family 

 which has the widest distribution is the amphibious OpUocephalidcB, which is likewise the one in which 

 true spines are the least developed. 



The Acanthopterygian Indian ft-esh-water forms probably had a marine ancestry, several of the 

 genera still having marine species, but not so the Carps. The most important genus of Indian carps is 

 Barhus, possessing about 70 representatives in India, a genus which is likewise found in Europe. 

 We find the largest forms ascending to the colder regions of the hills to deposit their ova : and the 

 species of the genus being of the smallest size in the hot plains where they breed : along with these 

 peculiarities we observe as a rule that similar to the European barbel, we have 4 appendages to the 

 mouth (barbels) in the large forms, 2 in those of medium size, but none in the smaller forms of the 

 plains. It would appear that it is not improbable that many genera of Carps are Palsearctic, their 

 type-progenitors having been derived from a northern ancestry : but there are others, as Romaloptera, 

 Fsilorhynchus, Semiplotm, Catla TkijnnicMhijs, Amblypliarijngodon, Aspidoparia, Bohtee, Chela and their 

 allies, which are no less of Oriental origin, and I hesitate to accept the theory that such are merely 

 modified northern genera. 



Respecting the scaleless Siluridj;, they as the Acanthopteetgii are perhaps modified marine forms. In 

 them the air-vessel or air-bladder possesses two distinct functional ofiices. In the Acanthoptertgians 

 where this organ is destitute of a pneumatic duct its use (excluding the question of its connection with 

 the internal ear) appears primarily to be a mechanical one, viz., for the purpose of maintaining a required 

 level in the water, and permitting the fish to rise or fall as desired. In the majority of carps (CtfriniDjE) 

 in addition to the foregoing function, a pneumatic tube connects it with the pharynx or upper portion 

 of the alimentary canal, and also a chain of ossicles with the internal ear. In fact, it serves both for 

 the purpo.se of hearing and also for flotation. But in the sheat-fishes (Sildkid^) the power of employing 

 this air-vessel as a float appears to be subservient to that of hearing. Living as they do the life of 

 ground feeders and mostly restricted to muddy localities, this organ is more usefully restricted to acoustic 

 purposes, while the feelers round their mouths permit them to move about with ease and safety, and 

 their organs of hearing to ascertain the vicinity of an enemy or the approach of some incautious prey. 

 In marine forms we meet with this air-vessel having a thick outer fibrous layer and attached to 

 the lower surface of the bodies and transverse processes of some of the anterior vertebrae, while a chain 

 of ossicles connects it to the internal ear. As however we pass inland or towards mountains, a change 

 occurs, the air-vessel being partially or entirely surrounded by bone. This may be effected by a trumpet- 

 shaped extension of the lateral processes of the first or second vertebra: or else by an expansion of the 

 most posterior of the auditory ossicles, but in either case the chain of bones is continued to the internal 

 ear. This being a modification of what we perceive in the Indian marine forms seems to lead to the 

 conclusion that it is through such that the fresh-water species may have been derived. 



Having briefly adverted to the fresh-water fish and fisheries, it becomes necessary to offer a few 

 remarks upon those of the sea. They not only exist in the open sea and along the coast, but so far as 

 tidal influence extends up large rivers, backwaters and estuaries. Opposite certain places on the coasts 

 of the ]\Iadras Presidency, vast mud banks are present, but they are so fluid as to enable many kinds of 

 fish to find abundance of food there, immunity from disturbance in the surrounding element such as exists 

 in the open sea, and an excellent locality for breeding purposes. 



Contrary to what obtains in the fresh-water fisheries, there is no paucity of the finny tribes in the 

 sea, but owing to some unfortunate cause, the harvest remains comparatively untouched. But before we 

 condemn the apathy of the native fishermen it will be as well to inquire whether a market exists for the 

 fish were they to capture them? or is the fisherman's occupation directly or indirectly affected by laws 

 and regulations rendering it impossible under present circumstances to carry on his trade in a profitable 

 manner ? 



If the fisherman has but a limited market for fish when captured, he naturally carries on his industry 

 where he can do so with the least amount of expense and toil, which must be effected by taking the 

 smaller kinds that can be dried with ease, and do not require a large outlay on salt. These smaller 

 fish prefer the vicinity of the shore where they obtain their food, but by destroying the small kinds 

 and the Crustacea, the fisherman is removing from the waters that which decoys the larger and more 

 predaceous ones in. As a result he scares away what should be the natural supply, and to the 

 uneducated eye the amount in the waters appears to have diminished. This does not concern the 

 fisherman so long as his trade supplies his family requirements, neither does it occasion much injury 

 if there is only a local demand and salt is not available for preserving the surplus. 



I do not intend adverting in this place to the various modes of fishing at present being carried 

 on along the coasts of India and Burma,* but purpose making a few remarks on the fishes of the 

 Indian Ocean. 



A considerable diflFerence is observable in the regularity with which certain large droves of 

 gregarious fishes as the mackerel {Scomber microlepidotus, p. 260) or the oil sardine {Clupea lonyiceps, p. 637) 



* See description in "JJeport on Sea Fisheries," 1873. 



