THE FLAT-FISH FAMILY 215 



the stomach and intestines of the plaice contain crushed shells 

 which it swallows with the shell-fish they belong to. But in 

 these cases the absence of shells was noticeable. After careful 

 scrutiny I satisfied myself that the fleshy lumps were the so- 

 called " feet " of the razor-shell Solen, and it is evident that the 

 plaice is able to seize the " foot " of this mollusc and bite it off*. 

 In other cases whole crushed Solens were present, but these were 

 usually smaller specimens. 



Time and Place of Spawning. In the North Sea, and in the 

 Channel, the plaice spawns at the beginning of the year in 

 January, February, and March. At Rothesay, on the Firth of 

 Clyde, according to Mr. George Brook, it spawns in April and 

 May. Off the Isle of May, Firth of Forth, eggs were fertilised 

 by the author on February 3rd. Mr. Holt considers it possible 

 that in the North Sea some plaice are still spawning in April or 

 even in May. At Plymouth none but spent females have been 

 seen after March. On the west coast of Ireland ripe females 

 were taken during the Survey in March and April, but none 

 later until August, and the record of these occurrences in August 

 is probably due to some mistake. 



The spawning of each single female occupies a certain time, 

 exactly how long has not been ascertained. It is known that 

 full fish, those which have only just begun to spawn, yield only 

 a few ripe eggs when squeezed, while those which have already 

 shed a good deal of their spawn give up very nearly the whole 

 of the remainder of the crop, and so supply a very large number 

 of eggs. This shows that the rate of spawning becomes faster 

 towards the end. At first a few eggs ripen and are discharged 

 from time to time, but towards the end a much larger number 

 are discharged in a short time. From observation of ripe speci- 

 mens in the Plymouth Aquarium it is known that a single fish 

 will take several days, from a week to a fortnight or even longer, 

 to get rid of all her eggs. 



With regard to the distribution of spawning fish, the places 

 at which they are found, it is known that they are not taken in 

 estuaries or shallow waters near shore, where the younger and 

 smaller fish abound in summer. They are taken in all the 

 deeper waters on shelly or partly shelly ground. The evidence 

 we have, not so abundant as could be wished, indicates that 

 large mature fish visit somewhat shallower waters when not 



