446 



A. Vedel Taning 



become high enough ( > 23°-24° C). Consequently, it is most pecuUar that post- 

 larval specimens were not taken during the Thor expedition in 1910, since consider- 

 able fishing was carried out with pelagic gear in July-August and in early September. 



Indo-Pacific. The Dana in 1928-29 carried out approximately 1650 hours of pelagic 

 fishing in the surface layers down to roughly 200 metres over wide areas of the Indo- 

 Pacific (Fig. 2). Almost all of the tows were made in areas where the water tempera- 

 tures were within the limits usual during spawning of this species. Nevertheless, only 

 a few young specimens were taken there. These provide a very incomplete picture 

 of the breeding areas and seasonal distribution. Except for a single specimen near 

 the Marquesas Islands in late September, all of the others are from the Indo-Malaya 

 region during the months of March, April, June, September and November or 

 practically throughout the year. 



As mentioned earUer, Lutken's specimens are undated so that they do not help to 

 clarify this point. However, the postlarval specimens of 11-27 mm in length from 

 the western Pacific mentioned by Yabe and Nakamura were taken from March to 

 May. Consequently, the season seems to correspond to that of the western Atlantic. 



VERTICAL DISTRIBUTION OF FRY 



It has already been noted that all the evidence points to the fact that the fry are 

 generally found in the uppermost water layers over deep water. The distribution 

 also suggests some connection with island areas (i.e. West Indies, Indo-Malaya, 

 East China Sea, Mediterranean). The reason may be that there is more food in such 

 areas than in the open ocean. Since we only have any significant number of Xiphias 

 fry from the western part of the North Atlantic, as previously pointed out, we will 

 delimit the water layers where the fry were taken in that area and consider the size 

 differences at various depths. The material included only two specimens over 2 cm 

 in length : one 33 mm in length, which was taken in a net which was fished at a depth 

 of approximately 30 metres, and one 46-3 mm in length which was taken in a dipnet 

 at night with a light. Therefore our discussion of vertical distribution will include 

 only a consideration of specimens of less than 2 cm in length. 



The 53 specimens ( < approximately 20 mm) caught in this area of the Atlantic 

 were taken in 43 hauls of the pelagic net. The number per tow was 1 specimen in 



Table II 

 Distribution of Xiphias fry according to number and size of specimens and 



the depth of towing 



* See p. 444 and footnote on that page for method of calculating fishing hours. The number of 

 fishing hours includes only those stations where specimens were taken. 



