136 Mr. A. Alcock on 



XXII. — Natural History Notes from H.M. Indian Marine 

 Survey Ship l Investigator ,' Commander T. H. Fleming, 

 R.N., commanding. — Series II., No. 25. A Note on the 

 Deep-sea Fishes, ivith Descriptions of some new Genera and 

 Species, including another probably Viviparous Ophidioid. 

 By A. Alcock, Surgeon-Major I. M.S., Superintendent of 

 the Indian Museum. 



Contents. 



§ 1. Introduction. 



§ 2. On some Geographical Relations of the Deep-sea Fish-fauna of 

 India. 



§ 3. General Composition of the Deep-sea Fish-fauna of India. 



§ 4. Descriptions of new Species, including another probably Vivi- 

 parous Species of Diplacanthojwma. 



§ 1. Introduction. 



In the Ann. & Mag. Nat. Hist, for November and December 

 1889, September and October 1890, January, July, and 

 August 1891, November 1892, and August 1895, and in the 

 * Journal of the Asiatic Society of Bengal ' for 1893, 1894, 

 and 1896, I have described the fishes dredged by the ' Inves- 

 tigator ' in depths ranging from 100-1800 fathoms during the 

 twelve years 1885-1896. 



In the present paper some noteworthy species dredged since 

 1896 are recorded ; though two of these (Raja Powelli, sp. n., 

 and Monocentris japonicus, C. V.) were taken at a depth less 

 than 100 fathoms, yet the occurrence of a temperate genus 

 like Baja close to the Indian shores, and the addition of 

 another singular Japanese species to the Indian fauna, are 

 sufficiently interesting to be noticed here. 



§2. On some Geographical Relations of the Deep-sea 

 Fish-fauna of India. 



In my earliest paper (Ann. & Mag. Nat. Hist., Nov. 1889, 

 p. 379) on the deep-sea fishes of the Indian region I drew 

 attention to the fact that several of our species were common, 

 on the one hand to the deeper waters of Madeira, the Medi- 

 terranean, and the Atlantic coasts of America, and, on the 

 other hand, to the seas of Japan. 



As Dr. Giinther had, long before, noticed the correspon- 

 dences between (1) the Madeiran, Mediterranean, and West- 

 Indian fish-fauna, and (2) the fish-fauna of Japan, and as at 



