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Part III. — Seventh Annual Report 



bands, and the embryo, even in spirit-preparations, can be distinguished 

 by the same pigment. 



Haddock. — An egg, resembling that of the haddock, appeared on the 

 2nd March, and had the embryo far advanced — with blackish pigment on 

 the skin. The ova of this species are common towards the middle and 

 end of the month. 



The larval haddock is 3 mm. in length, and has black pigment-corpuscles 

 somewhat densely grouped behind the otocysts, and extending backward 

 a little beyond the commencement of the intestine. A line of the chroma- 

 tophores passes along the infero-lateral region from the beginning of the 

 mesentery to near the caudal tip, and a few appear on the lower part of the 

 abdominal region. A delicate polygonal protoplasmic mesh -work occurs 

 over the surface of the yolk as in the flounder. 



Rockiing (Motella). — The ova of Motella in small numbers were 

 obtained occasionally from the 2nd March to the 18th May, being most 

 plentiful at the end of April. As a rule, they appeared in the mid-water and 

 bottom-nets, though an ovum, measuring *04 inch, with an oil-globule 01, 

 was captured in the surface-net on the 20th May, and probably belongs to 

 the same genus. They are often plentiful in the bottom-net in spring 

 That procured in March had the embryo fairly advanced, the eyes being 

 outlined, but the tail was short. In January 1885 many rocklings 

 spawned in the tanks in the laboratory, and specimens continued to 

 do so till March. Ripe females occurred in the tanks till April. 



W/ritinr/. — Ova of the whiting are common in April. 



Lump-Sucker. — Larval examples appeared on the 11th June, and 

 several times (in all 4 times) subsequently, viz., till the 20th of July; 

 their length was 5 # 6 mm. 



POST-LARVAL FORMS OF FOOD-FISHES, &c. 



During the months of January, February, March, and April (with the 

 exception of the last few days of the latter), no young round fishes were 

 observed, if we except a few sprats on the 20th January and 12th April. 

 Again, for the last week in April to the 20th September, post-larval food- 

 fishes abounded ; only Clupeoids occurring after the last mentioned date. 



On the other hand, in 1889 post-larval forms of various kinds were 

 procured from the middle of February. 



Generally speaking, the sizes of the pelagic forms do not increase as the 

 months go by, apparently for the reason that the larger forms seek down- 

 ward or migrate elsewhere as they grow. 



In the pelagic phase of larval and post-larval fish-life many forms which 

 issue from demersal eggs are included, and the importance of these is 

 greater than at first sight appears, since they serve as nourishment for the 

 more valuable kinds, such as the food-fishes. It is true that some of 

 these, such as the young lump-suckers, are very active and voracious, 

 darting hither and thither to snatch smaller fishes than themselves, but 

 in turn they are preyed on by the larger kinds — which frequent the margins 

 of the rocks, or find the young lump-suckers amidst the floating masses of 

 sea-weed in the long tidal lines at a distance from shore. 



Pleuronectids. — These made their first appearance on the 20th January, 

 and measured f inch, None were captured between this and the 26th 

 April, and only once in June. In May, July, August, and September 

 they occasionally occurred, most being procured in the latter month. 

 Three or four were brought up in the net on each occasion, and the 

 number of times was 17. Their last appearance was on the 18th 

 September. The length of these varied from 5 to 13*5 mm. 



