190 



MESSRS. E. W. L. HOLT AXD L. \V. BYRNE — BISCAY AN PLANKTON ; 



that, to determine m itli any accuracy the vertical range of the ova and larvse of fishes 

 whicli live at or near tlie surface over deep soundings, hauls must be made with closing 

 tow-nets through short distances in the surface-waters, particularly, we think, between 

 100 and 25 fathoms. Dr. Fowler's results seem to show that fish-larvae are uncommon 

 at the surface, and even between 25 fathoms and the surface ; but between what depths 

 in the succeeding 75 fathoms they are found, and whether there is any difference in 

 vertical habitat between the larvse of different species, remains yet to be investigated. 



In tlie succeeding pages we shall first discuss the vertical distribution of the ova and 

 larvae n.'corded as a whole, secondly give a list in systematic order of the species of fish 

 met witli, together with the vertical distribution of fishes with adult characters, and lists 

 under each species of recorded occurrences during the cruise. 



II. The Vertical Distribution of Ova and Larv.^;. 



Though Dr. Eowler's nets naturally took only fishes of small size, it seems advisable 

 to treat the ova and larva? at first separately from those forms which, though small, had 

 attained the adult conformation, and subsequently to treat the question of the vertical 

 distribution of the adults when dealing with the individual species ; in the case, how- 

 ever, of ova and larvse, the number of more or less spherical objects submitted to us as 

 possibly fish-ova, Avhose exact nature it has been impossible to determine, and the 

 numerous larvse, whose parentage and appearance in life cannot even be conjectured, 

 make it impossible to treat the question of distribution otherwise thau in the most 

 general terms. 



The following table shows the number and percentage of hauls in which " ova " and 

 larvgp occurred : — 



* In one of these hauls the catch was a Oonostoma microdon of IS mm., perhaps hardly a larva. 



