238 MARKETABLE RRITISH MARINE FISHES 



Island on May 22nd, and by Prof. Mclntosh in August. On the 

 south-west coast the author obtained a few ripe eggs from 

 March 5th to 8th. Fertilised eggs were obtained throughout 

 April and May. Spawning commences in February, many ripe 

 females having been observed in the market on February i8th, and 

 one was also observed as late as July I5th. March, April, and 

 May are however the principal months on the south-west coast, 

 so that the spawning is there two months earlier than on the 

 north-east coast. 



No special grounds have been yet observed to be preferred 

 by lemon dabs in the spawning condition. The ripe specimens 

 are found on the grounds on which the adult fish are taken at 

 other times of the year. These fish have not been found to move 

 towards shallower inshore waters after the spawning season, as 

 plaice and soles and other kinds do to a certain extent. 



The Eggs. The egg of the lemon dab is spherical and 

 measures after fertilisation from 1*36 to 1*44 mm. according to 

 observations at Plymouth (y^nnr to T ^<j- inch, or a little more 

 than -J-Q inch). It is smaller than that of the plaice but larger 

 than that of the flounder or dab. It can scarcely be dis- 

 tinguished from these other species except by its size, resembling 

 them in the undivided yolk and absence of oil globule. Con- 

 siderable attention was devoted to the study of these eggs at 

 Plymouth in 1888. The temperature of the sea in April and 

 May, near the Eddystone and the Wolf Rock where the fish was 

 spawning, was from 43'5 to 50. At a higher temperature in 

 the laboratory, namely 53 to 55, the eggs hatched six days 

 after fertilisation. In the sea their development would probably 

 have taken eight or nine days. In more northern waters the 

 time required would be somewhat longer. The specific gravity 

 of the eggs was found to be about ro24 ; in water of density 

 1*025 they floated, in that of density 1*023 they sank to the 

 bottom. The density of the water about the Eddystone at the 

 temperatures above given was 1*0267. 



The Larval Stages. The larva when first hatched is 3-8 mm. 

 in length (,-yVu inch, or nearly f inch). It is somewhat narrow 

 and slender in shape. The pigmentation is slight, and consists 

 of very light yellow and black specks. There is no definite 

 arrangement of these, they are scattered over the primitive fin, 

 the sides of the body, and the yolk sac. Fig. no represents a 



