of the Fishery Board for Scotland. 
VIIT. NOTES ON THE DEVELOPMENT OF THE ANGLER-FISH 
(Lophiuti piscatorius). By Professor E. E. Prince, B.A., F.L.S. 
(Plates XIV., XV.) 
The development of Lophius piscatorius has been referred to by Professor 
J. A. Ryder as "one of the most extraordinary yet known to enibryologists," 
and certainly the eggs and larva) present features of peculiar interest. The 
species is of common occurrence upon our coasts ; but hitherto no British 
observer has secured the ova or reared the young through their larval stages. 
This is the more remarkable because the eggs float in large masses in the 
sea, and, unlike most pelagic ova, would appear to be especially exposed 
to observation. Alexander Agassiz, nearly twenty years ago, recorded 
that he was familiar with these eggs, and that they occurred on the surface 
of the sea in the form of "a gigantic mucous band." This egg-band, 
according to Agassiz and Whitman (2, p. 17,) is of a violet-gray colour, 
and somewhat blackish, on account of the dark pigment present in the 
young embryos. On the Irish and Scottish coasts such egg-masses have 
occasionally been seen, and an example was discovered by Mr Thomas 
Scott, F.L.S. , stranded on the beach to the east of the Flagstaff on Elie 
Ness, in July last. It was between twelve and thirteen yards in length. 
Recently two further specimens have been obtained by the Fishery 
Board for Scotland. One of these ^vas secured off Kinnaird Head on 
February 18th, and measured 36 feet in length, while its depth varied 
from 10 in. at the centre to 6 in. at the ends. Its thickness was 
stated by its captor to be barely -^^ in.; probably after dessication, 
for the diameter of the ovum is rather less than ~ in. and the 
enfolding mucus is said to be twice the diameter of the egg. When 
the specimen came into the hands of Mr Melville, Fishery Officer, Fraser- 
burgh, the eggs were observed to be " arranged somewhat like the meshes 
of a herring-net, with a very thick skin protecting both sides of the 
globules " — this skin being, no doubt, the dried layer of mucus in which 
the ova are enclosed."^ Arranged as they are, in a single layer, the mass 
assumes the form of a flexible ribbon. Dr Fulton, Scientific Secretary 
to the Fishery Board, when forwarding to Professor M'Intosh portions of 
the egg-band referred to, stated that the dried jelly was almost invisible . 
when the specimen reached him, but ''swelled up and became a little 
opalescent on being moistened with fresh water two days after." The 
specimens, unfortunately, were not favourable for study ; but other 
material sent by Dr Fulton to St Andrews became available when, in 
February, a second mass of the eggs of Lophius was secured in the 
Firth of Forth. Its dimensions seem to have been almost precisely the 
same as those of the Fraserburgh specimen, and portions were forwarded 
to the St Andrews Marine Laboratory, where, through the kindness of 
Professor M'Intosh, a preliminary study has been made of the embryo 
in ovo, and of the emerged young of the first day, and of larval examples 
five, nine, and fifteen days old — a few specimens of these stages accom- 
panying the ova. The amount of material for study was limited ; but as 
some of the specimens were in fair preservation, the elucidation of 
certain interesting points in the structure of the curious embryo of Lo- 
phius was rendered possible. 
* If any true membranous sheath envelopes the mass of eggs it must be of great 
transparency and delicacy. No reference to such is made in published descriptions 
of fresh ova in Irish and American waters. 
