THE present work is chiefly an abridgment of the author's "Fishes of India,' published in 1876-78. Several additions and alterations have been made, most of which were pub- lished in 1888, in a Supplement to the work just mentioned. The synonymy, having been already quoted in full, has not been repeated in these volumes, but under each species will be found a reference to the original specific description, and to the page in the Fishes of India' where full details are given. The illustrations in the present work are, with very few exceptions, copies of those in the Fishes of India." The state of Dr. Day's health has unfortunately prevented him from correcting the proofs of the present publication beyond the middle of the first volume, and it is probable that some mistakes or omissions may have escaped detection in consequence. The manuscript of the work had been prepared before the author's health gave way; but some additional compression was required, and this the editor has carried out to the best of his ability. The limits of the area of which the freshwater fauna is here described have been already defined in the Introduction to the volume of Mammals belonging to the same series ("The Fauna of British India'), and are those of British India and its dependencies, such as Burma, the Andaman and Nicobar Islands, Manipur, Nepal, Kashmir, Baluchistan, &c., ogether with Ceylon. The marine fishes included are all nown to inhabit the seas around British India.