11 



"Since 1885 the Zoological collections rande by the ' Investig-ator ' have been accumulat- 

 ing' yenr by year in the Indian Museum, where, in accordance with the recommendations of the 

 Council of the Asiatic Society of Bengal, they have been deposited. 



"It must not, however, be supposed that deep-sea dredging occupies a very large part of 

 the attention of the officers of the Survey ; since, as a rule, it is only possible when the ship 

 is proceeding to and returning from her systematic surveys of tlie shores and shallows. It is 

 nirely indeed that as many as twenty deep-sea hauls are made in one year. 



" From October 1888, when regular records began to be kept, up to the present time, 118 

 more or less successful hauls have been made in depths of over a hundred fathoms (100-1997 

 tins.). 



" As regards the ' Investigator ' herself, she is a paddle-steamer of 680 tons, and for a few 

 facts as to her liistory and equipment I may refer to a paper in the Scientific Memoirs of the 

 Medical Officers of the Army nf India for 1898." 



"With regard to the contents of the present vohime on the Deep-Sea Fishes, 

 I may state that the species not here described for the first time have ah'eady 

 been noticed in the following papers : — 



JouEN. As. See. Bengal: Vol. LVIII. pt. 2, 1889, pp. 279-295, pi. xvi-xviii, 

 and pp. 296-305, pi. xxii; Vol. LXIII. pt. 2, 1894, pp. 115-137, pi. vi-vii ; and 

 Vol. LXV. pt. 2, 1896, pp. 301-338. 



Ann. Mag. Nat. Hist., (6) IV. 1889, pp. 376-399 and 450-461 ; (6) VI. 

 1890, pp. 197-222, pi. viii-ix, and pp. 295-311 ; (6) VIII. 1891, pp. 16-34 

 and 119-138, pi. vii-viii ; (6) X. 1892, pp. 345-365, pi. xviii, and pp. 207-214; 

 (6) XVI. 1895, pp. 144-146; and (7) II. 1898, pp. 136-156. 



Peoc. Zool. See. 1891, pp. 226-227. 



All but four of the new species described in the above-cited papers have 

 been figured in the Illusteations of the Zoology of the K. I, M. S. Investigator, 

 Fishes, pis. I-XXVI (and XXVII-XXXV in the press). 



As it is intended that those plates should be bound up with the present 

 Catalogue, together with a small a23i3endix on the Shore Fishes discovered by the 

 Investigator, no special illustrations have been prepared for this volume. 



I have however added (facing page 12) a chart, compiled from plate ii of 

 Dr. Ernst Koken's Die Vonvclt uiid ihre EnfivlclThivr/sgi'SchicJ'Jf, which is meant 

 to elucidate the theories upheld in the Investigator Eeports as to the origin and 

 past geographical relations of the fauna of the Indian Oligobenthus. 



For the opportunity of making this chart and for help in compiling it, I am 

 jndebted to Mr, T. H. Holland of the Indian Geological Survey. 



To explain an apparent want of uniformity in the plan of this Catalogue, 

 I must mention that I have intentionally omitted diagnoses of the families and 

 genera, and of the one or two species, heretofore well known to inhabit Indian 



