Ocmrrence of Sheets of Spaivn. ^1 



been formed. Further, during the development of the first dorsal fin, the membrane 

 connecting the elongated rays rises very high between them, so that the depth of 

 the larva is considerably increased, also without much additional weight. Thus, 

 the great development of these structures along the median line of the body gives 

 the young fish much greater stability whilst living in the upper water layers. This 

 stability is still further increased by the enormous development of the paired pec- 

 toral fins which are expanded fan-like and attached high up on either side of the 

 body. 



In short, the morphological changes through which the Angler passes during 

 its early life-history must be regarded rather as adaptations to a pelagic mode of 

 life than as structures reminiscent only of pelagic ancestors, and that only after 

 an extended period and when the young fish has reached a considerable size do 

 retrogressive changes bring about a form suited to life at the bottom. 



The Occurrence op the Sheets of Spawn. 



Notwithstanding innumerable investigations carried on, especially in recent 

 years, over the extensive area in which adult Anglers are caught, the number of 

 published records of the occurrence of the spawn of the Angler, and of its larval 

 and post-larval forms, is strikingly small. The few isolated records are from areas 

 very widely separated ; the east coast of America, the North Sea, the English 

 Channel, and the Mediterranean in the neighbourhood of Naples. No satisfactory 

 explanation has been offered why the records of such a conspicuous object as the 

 spawn of the Angler are so few. Agassiz (1882), who was the first to describe the 

 appearance of the spawn, gives no information as to the frequency of its occurrence 

 on the American side of the Atlantic. Gill (1905), however, in his story of the life 

 of the Angler, makes the following statements : — " About the end of summer, the 

 fishes seek shallower water, and the inhabitants of the depths advance upwards ; 

 the sexes must then consort together, but in what manner and what rites of marriage 

 are performed is unknown ; the result, however, is that about the time indicated, 

 the fishermen on the New England coast often notice a substance floating on the 

 water, which they term a ' purple veil.' " It would appear from this statement 

 that the spawn is not infrequently met with, since the fishermen have coined a 

 popular name for it, and it is, therefore, of interest to have a more recent and 

 definite record from this area, by Murray and Hjort (1912). During the voyage of 

 the Michael Sars across the Atlantic, a large cluster of Angler eggs was found at 

 Station 69 (41" 39' N. ; 51° 4' W.), from which the embryos were hatched. " Angler- 

 fish only inhabit the coast-banks, so that our find of slightly developed eggs that 

 could not have been drifting many days indicated that we were now in the neigh- 

 bourhood of the American coast." 



Scottish Records of Occurrence of Spawn. 



Definite records of the occurrence of the gelatinous bands have been 

 made mainly by Scottish workers, but when all the records are collected, they 

 do not form a very imposing list. Prince (1891) says that egg-masses have 

 occasionally been seen, and Mr. (Now Dr.) Thomas Scott, F.L.S., foimd a mass of 

 spawn stranded on the beach east of the flagstaff on Elie Ness, in July (presumably 

 July 1890). It was between twelve and thirteen yards in length. Later, two 

 additional specimens were obtained by the Fishery Board for Scotland. One was 

 secm-ed off Kinnaird Head on 18th February 1891, and Fulton got a second mass 

 of eggs of Lophius in the Firth of Forth in July 1891. Another large mucoid band 

 was obtained by Fulton (1902) in a trawl haul made in Aberdeen Bay on the 1st 

 August 1901, in 8 to 12 fathoms. The embryos were far advanced, and some indeed 

 had already hatched out. 



M'Intosh and Masterman (1897) state that the masses are sometimes caught 

 by the ropes and nets of the salmon stake nets off' the east rocks at St. Andrews, 

 On 10th July 1891, a considerable portion of the gelatinous mass containing the 

 ova of the Angler was found in the stake nets off the East Rock, having apparently 

 been swept in by the currents and entangled in the meshes. 



M'Intosh and Prince (1890) in a footnote refer to the rarity of the floating ova 



