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on a trawler to llie west of tlie EtUl3'stone on February G, I cot a few, verj- 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 ihe 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 ^larch 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 Pl3niioutli on March 8, I found only 

 about a dozen ova floating, and of these onlj' 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 rij)e eggs altogether, 

 but onlj' a few from each fish. From May 1.5 to 18, when I was in a trawler on 

 the same ground, we had verj' 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 1888 that the artificial fertilisa- 

 tion of soles' ova was a matter of the greatest difiiculty. 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 traAvl, 

 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 ofl' Eooe to a ])oint 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 

 I'ddystone. 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 

 Xewl3Ti mackerel boats were working small trawls in Mount's Baj" 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 tlie testes very carefully. I tried a large number of males, and could not 

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



