356 THE FLOUNDER FAMILY. 



of red or brownish pigment occurred along the dorsum, two in 

 the dorsal marginal fin and one on the trunk behind the vent. 

 He followed the larva into the post-larval stage, with the long 

 dorsal process from the head (Plate XX, fig. 3), then into the 

 metamorphosed condition of 16 — "18 mm. in August. Petersen 

 found one of 23 mm. with scales. 



Cunningham obtained small specimens in shallow water 

 (3 — 5 fathoms) near Plymouth in October, their length being 

 from an inch to 1'4 in. and he thought them 4 — 5 months old 

 (Plate XIV, fig. 13, after Holt). In February they were from 

 1'8 to 2'5 inches, and then probably from 8 — 9 months old. 

 They reached 1'9 in. in May at the age of 11 months. The 

 following February they occurred in deeper water 3'7 to 47 

 inches, and he estimated the age 1 year and 3 months. In 

 September many of 3 to 5 inches were procured also in deeper 

 water, and he considered these a year and three months old. 

 They were sexually mature at 5 '8 inches, and these he states 

 were over two years. The adult males are easily recognized by 

 the sudden elongation of the anterior dorsal fin-rays. Like 

 other flat-fishes the young seek the shallow sandy margins, 

 migrating outwards as they grow older, and being especially 

 abundant in the south between 20 and 30 fathoms. 



Holt, again, mentions several of 25 mm. trawled at 41 

 fathoms in August, off Ballycottin, Ireland. Black pigment is 

 distributed in small dots, in patches on the jaws and head, and 

 a line of chromatophores runs along the base of the inter- 

 Hpinous ridges. Streaks of black occur at intervals along the 

 rays of the dorsal and anal fins, and two patches on the caudal 

 fin. 



From the west coast of Ireland occur specimens from 2f to 

 31 inches in length in the month of July. By Cunningham's 

 estimate these should be about a year old. 



The Plaice. {Flevronectea platessu, L.) 



This fish is perhaps the best known of the flat-fish group, 

 and it has also the earliest spawning-period. Quite at the 

 commencement of the year, towards the end of the first month, 



