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Part III. — Seventh Annual Report 



caught; and in one haul a considerable number of witches (P. cynoglossus) 

 and lemon dabs (P. microcephalics), but few of these were large. Plaice 

 were remarkably scarce in the Moray Firth. Mr Scott succeeded in fer- 

 tilising a few plaice ova, and also tried the effect of cod milt on plaice 

 eggs. He states that about half an hour after the contact of the milt a 

 slight depression appeared on the side of each of the plaice eggs, but after 

 some were placed in Perenny's fluid they resumed their normal contour. 

 Their appearance some hours afterwards 'seemed to show that development 

 had proceeded to a slight extent.' These eggs, after the cod milt was 

 added, lost their buoyancy and sank to the bottom (probably the indent- 

 ation and descent were due to alteration of specific gravity). 



The surface tow-net caught a considerable number of pelagic fish ova 

 so far developed that the eyes of the young fish could be plainly seen 

 with the naked eye. The surface temperature ranged from 41° F. to 43° '1 

 F. ; but this difference did not affect the numbers of floating eggs. Mr 

 Scott learned that haddocks, as well as cod, spawn in great numbers in 

 the Moray Firth at the end of March and the beginning of April. 



VI. Moray Firth. 



The third visit to this important area took place between the 26th and 

 29th March. Very stormy weather was experienced. Eleven hauls 

 were made about 12 miles or so north-east of Lossiemouth. The 

 great bulk of the catches consisted of haddocks, the large ones 

 ranging from about 14 to 24 or even 27 inches in length, the medium 

 sized ones being an average 13 or 14 inches long, but ranging from a few 

 at 10 inches to 14 inches. Altogether about 100 boxes of large sized 

 haddocks and about 50 boxes of medium sized haddocks were obtained. 

 The great majority of the haddocks were ripe and spawning. The most 

 abundant flat fish was the witch sole or long flounder (P. cynoglossus) 

 (about 14 boxes), and the next the lemon sole (P. microcephalus, 

 (about 2 boxes). Considerable numbers of the long rough dab 

 (Ilippoglossoides limandoides), the common dab (P. limanda), monk-fish, 

 cod, and whiting were obtained ; also a few ling, hake, skate, saithe, 

 &c. Comparatively few plaice were taken, not indeed enough to fill a 

 single box from the 11 hauls. The depth varied from 20 to 40 fathoms, 

 and the temperature of the surface water from 40° *2 F. to 42° *8 F. In 

 regard to the prevalence of pelagic fish ova, this expedition, like the 

 one in January, was noteworthy. The bottom-net contained chiefly 

 Schizopods, and a few Saggitoe, and Ccdanus; but the surface-net contained 

 enormous quantities of fish ova ; Mr Scott remarks that he never saw 

 pelagic ova so abundant. The greater proportion were haddock ova, 

 no doubt derived from the shoals of ripe haddocks revealed by the 

 trawl-net ; but cod ova also were present. Some of the latter obtained 

 on the 27th hatched out on the 29th, the young fish exhibiting the 

 peculiar and characteristic banded appearance. Mr Scott, referring to 

 the young cod, says : — ' I find that as soon as the young fish hatch out 

 ' they seek down, but whether they proceed to the bottom or nor I have 

 1 not been able to discover.' 



Mr Scott artificially fertilised some ova of the haddock on the 27th, 

 about 2 p.m., and on the 31st, at 10 a.m., the outline of the embryo fish 

 could be clearly made out. He points out that in the case of the plaice 

 ova 8 days elapsed before the outline of the embryo could be made 

 out, and indicates that haddock ova, therefore, appear to hatch much 

 sooner than do the ova of the plaice. 



Of the few ling obtained, a female was found quite ripe, a cupful of 



