686 REPOBT — 1891. 



known to he not less tlian a year old, are from 12 to 19 cm. in length. None of 

 these captive flounders nor any taken in the Cattewater were sexually mature, but, 

 accordino-to Dr. Fulton, of the Scottish Fishery Board, sexually mature flounders 

 have been observed which were only 7 inches long. I conclude therefore that (a) 

 the rate of growth varies greatly for different individuals, but its maximum for the 

 first year is 19 cm. or 7^ inches, (b) sexual maturity is not reached till the end of 

 the second year, although the minimum size of sexually mature individuals may be 

 slio-htly exceeded by some specimens in one year's growth. 



I have obtained similar results for the Plaice (PL platessa) and the Dab {PI. 

 limanda). 



(2) Distribution. — The young of the above-mentioned species in their first year, 

 and of certain round fish, especially Gndus liiscus and G. 7mnutus, occur in shallow 

 water, within the 10-fathom line. But there has hitherto been considerable diffi- 

 culty in obtaining young specimens of other more valuable species in order to study 

 their rate of growth. These species, namely, the Sole, Turbot, Brill, Lemon Sole, 

 Megrim {Anioglossus megastoma), do not pass the first year of their lives in shallow 

 water. I have obtained young Soles in the larval state in tidal pools at Mevagissey, 

 and young Turbot and Brill 2 to 3 cm. in length are commonly found from June to 

 August in Plymouth Sound and Sutton Pool, swimming at the surface in a semi- 

 metamorphosed stage. Soles a little over IG cm. in length are frequently taken in 

 Plymouth Sound in summer ; these are just over one year old and are not sexually 

 mature. Turbot 2.3 to 34 cm. long I have taken in 5 to 7 fathoms ; these also are 

 over one year old and not sexually mature. But the yoimg stages between 3 

 months and 12 months old have not been taken in shallow water, and apparently 

 live at depths greater than 10 fathoms. It seems that our commoner and more 

 valuable food-fishes do not attain to sexual maturity till the end of their second 

 year, that their size at this age is subject to great individual variation, and that 

 the young in the first year of growth have a characteristic distribution. Investiga- 

 tion of the deeper water from this point of view is now being carried on at 

 Plymouth. 



6. The Bejoroduction of the Pilchard. By J. T. Cunningham, M.A. 



In a paper published in the ' Journal ' of the Marine Biological Association in 

 1889, 1 described the egg of the Pilchard, obtained from the sea by the tow-net, 

 and identified by comparison with the mature egg taken from ripe female Pilchards. 

 The distinguishing features are four in number: (1) size r6-') to 172 mm. in 

 diameter, (2) the very large perivitelline space, (3) the vesicular composition of 

 the yolk, (4) the large single oil-globule in the yolk. 



Professor Pouchet, who has studied the Sardine at the Marine Laboratory of 

 Concarneau, persists in denying that this egg obtained by me is that of the Pilchard, 

 believing that the egg of the Sardine or Pilchard is not pelagic.^ My identi- 

 fication confirmed that suggested by Raffaelle from observations at Naples. Marion 

 at Marseilles ^ has entirely confirmed my results and also traced the growth of the 

 Sardine at that place, showing that it reaches a length of 9 to 13 cm. in one year. 

 This year at Plymouth, in June, I obtained ripe female Pilchards, but no males. 

 However, 1 placed the ripe unfertilised ova in clean sea-water, and found that after 

 twenty-four hours the ova were alive and floating, the perivitelline space was 

 formed, and the eggs presented all the characteristic peculiarities I had previously 

 attributed to the ova of the Pilchard. I also at the same time obtained the same 

 eggs in process of development from the sea, by means of the tow-net. In July I 

 obtained the alevins of the Pilchard at the surface near the Eddy stone, a number 

 of specimens varying from -8 to 2-5 cm. in length. I hope to trace their further 

 growth and compare it with that of the Mediterranean Sardine. The ripe Pil- 

 chards at Plymouth are 23 to 25 cm. long, ripe adult Sardines in the Mediterranean 

 are only 15 to 18 cm. 



' See ' Rapport sur le Lab. de Concarneau for 1889,' in Journal d'Anat. et de 

 Physiol., 1890. 



* Ami/lies du Mvsie d^Hintoire Nat. de Marseille, 'Zoologie Appliqu6e,' 1891, 



