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on a trawler to the west of the Eddystone on February 6, I got a few, very few, 

 ripe ova, and could get no milt by squeezing any of the fish. I did not then know that 

 the testes were small and the milt small in quantity in die sole. Only two or three of 

 the ova then obtained were found to be floating in my bottles when I returned to shore, 

 and none of these were fertilised. My next attempt was on March 6 and 7, when 

 I was on a trawler to the S.E. of the Wolf Eock. Only two or three females out of 

 nearly a hundred were then found to yield ripe ova, and as I could squeeze no milt 

 from the males, I cut out the testes, cut them into two or three pieces and placed them 

 in the bottles with the ova. On my return to Plymouth on March 8, I found only 

 about a dozen ova floating, and of these only two or three were fertilised and showing 

 the commencement of development. I made another attempt on the same fishing 

 ground between April 3 and 7, but on my return found that not a single ovum 

 was fertilised. On this occasion I got a considerable number of ripe eggs altogether, 

 but only a few from each fish. From May 15 to 18, when I was in a trawler on 

 the same ground, we had very bad weather : nearly all the soles were spent, but some 

 ripe ova were obtained from one specimen, and three or four of these were found to 

 be fertilised by the pieces of testis. 



It seemed therefore from these experiments made in 1 888 that the artificial fertilisa- 

 tion of soles' ova was a matter of the greatest difficulty. T had succeeded in ascertaining 

 the characters of healthy fertilised ova from the few I had been able to procure, and 

 was therefore able to identify the sole's ovum when it occurred in the produce of the 

 tow-net, and I had also observed and made drawings of some stages of the development, 

 but this, though valuable knowledge, brought me very little nearer to the practical 

 object of my experiments. 



In the season of 1889 I continued the experiments. I had found that soles were 



scarce on the Plymouth trawling ground, which extends from the Dodman Point in 



Cornwall, to the neighbourhood of Bolt Head in Devon, both inside and outside the 



Eddystone. On this ground very often no soles at all are found in a haul of the trawl, 



and when there are some very often all are immature, or when a ripe female is taken 



there are no males. On February 12, 1889, I was on a trawler which towed her trawl 



from off Looe to a point south of the Plymouth Breakwater lighthouse : four soles 



were taken in this haul of which only one was adult, and that not ripe. On March 14, 



I went out again, and this time the trawl was worked about 10 miles south of the 



Eddystone. Two hauls were made : in the first there was one sole, in the second none, 



although the first haul was made in the night. After this I heard that some of the 



Newlyn mackerel boats were working small trawls in Mount's Bay in order to earn 



something while waiting for the commencement of the mackerel season. I therefore 



went down to Penzance by rail, taking with me a number of collecting bottles to bring 



back soles' ova. I went out in one of the boats on March 22. On this occasion I 



examined the testes very carefully. I tried a large number of males, and could not 



squeeze from any of them the thick milk-white milt which is so characteristic of the 



