OCCURRING IN THE NEIGHBOURHOOD OF PLYMOUTH. 13 



and both kinds are abundant on the surface of the yolk. The noto- 

 chord is multicolumnar, and the anus immediately behind the yolk. 

 But the most peculiar feature in the larva is the great size of the 

 rudiment of the pectoral fin. As usual the mouth is not open, but 

 there is an opercular opening leading to the gill-slits. The larva 

 was 3"7 mm. in length. 



Pleuronectes miceocephalus. 



I first got the eggs of this species, along with those of the sole 

 and others, on March 5th and 6th, 1888, when I was on board a 

 trawler which was fishing to the south of the Wolf Rock, which lies 

 to the west of the Lizard Point in Cornwall. In the spring and 

 summer, with few exceptions, all the Plymouth trawlers are accus- 

 tomed to fish in that neighbourhood. They usually leave the port 

 of Plymouth on Monday morning, about 8 a.m., and as a rule it 

 takes about twenty hours to sail to the fishing ground, which is 

 usually spoken of by the fishermen as Mount's Bay, although the 

 fishing actually takes place some distance to seaward of any limit 

 which could reasonably be defined for that bay. Several times I 

 went on board one of tlie trawlers named the " Lola," and collected 

 eggs of all the species of fish which were in a ripe condition amongst 

 those brought on deck during the week's fishing. Each boat usually 

 returns to Plymouth on Saturday, and starts again the following 

 Monday. 



My first trip lasted only from March 5th to March 8th, as we 

 were obliged to return to Plymouth before the end of the week on 

 account of bad weather. On that occasion I found one or two 

 specimens of PI. microcephalus which were partially ripe, and got a 

 few ova and a little milt; but when I examined these ova afterwards 

 on shore I found they were either dead, or still living and floating, 

 but unfertilized. My next trip lasted from April 3rd to April 7th, 

 when I again got some eggs of the same species, and found on my 

 return that they were not fertilized. On April 11th the fisherman 

 engaged for the collecting work of the Association was sent by me 

 to go out in a trawler fishing on the Plymouth ground, and try to 

 procure some fertilized ova. He returned on April 13th, bringing 

 ova of PL microcephalus but of no other species. These ova I found 

 were fertilized ; they were taken four or five miles south of the 

 Eddy stone, the trawl being towed east and west. The Laboratory 

 fisherman went out again in a trawler on April 23rd, the boat fished 

 in the Irish Sea about forty miles north of the Longships Light- 

 house. He brought back on April 28th ova of PL microcephalus, 



