Occurrence of Post-Larval Forms. 2T 



way with that for those of the North Sea. It is well known that, for a species 

 with such a ^vide distribution, spawning occurs earliest in the south, and' gradually 

 gets later and later towards the north. (For example, the Hake, which has a dis- 

 tribution very similar to that of the Angler, spawns much earlier in the Mediter- 

 ranean than west of the British Isles.) The only definite record of the spawn 

 between the widely-separated areas, the Mediterranean and North Sea, is the one 

 given by Cunningham for Plymouth. The spawn was got in June with the embryos 

 far advanced in development. Hence, one may say, with some degree of confidence, 

 that the spawning of the Angler in European waters begins at least as early as 

 January in the Mediterranean, and gets later and later further north. In the 

 Scottish area, spawning begins at least as early as March, and extends to the last 

 weeks in July. 



The Occuerence op the Post-Larval Forms. 



There is only a single record of the capture of a larval form in the North 

 Sea. This specimen was taken by the Goldseeker at 58° 26' N. ; 0° 8' W. on 

 the 15th July 1914. The absorption of the yolk was almost complete. 



The time and place of occunence of the post-larval stages in Scottish waters 

 agree with what has already been stated concerning the spawning. The records 

 are most numerous for the months of July and August, so that the height of the 

 spawning season in Scottish waters probably occurs in the month of June. Further, 

 most of the post-larval forms were got north of 58° North Latitude, but the greater 

 number of these specimens was caught in the lower water layers, in contrast to the 

 isolated eggs which were taken mainly at the surface. 



The oldest post-larval form from the North Sea, which measured 16 mm., was 

 captured at 57° 17' N. ; 1° 3' W. in a Petersen Young Fish Trawl fishing in a depth 

 of 103 metres on 11th September 1909. This post-larval form had the six rays 

 in the first dorsal fin, and the second dorsal and anal fins were completely formed, 

 the rays extending to the margin of the embryonic fins. The pectoral and pelvic 

 fins had also attained their extraordinary development. The other specimens, 

 which had reached a similar degree of development, were captured in the month 

 of August in the Atlantic, north-west of Scotland. 



There are one or two previous records of post-larval Anglers from Scottish waters 

 which may be referred to here. There is the post-larval specimen described by 

 M'Intosh and Prince (1890), which was caught in 25 fathoms, 15 miles ofi May 

 Island, on 30th August 1886. It is a mutilated specimen, which, from its size and 

 description, is probably a young post-larval form in which the second dorsal and 

 anal fins have not yet appeared. 



Another specimen from Scottish waters was caught by WilHamson (1909) in 

 Loch Fyne, near Otter, in a tow-net worked horizontally about five fathoms below 

 the surface, on 28th July 1899. The specimen preserved in spirit measured about 

 7 mm., and it had two dorsal filaments developed on the head. It is, therefore, 

 a very yoimg post-larval form. 



The detailed fist of larval and post-larval stages captured in Scottish waters 

 is given in the following table : — 



[Table. 



