OCCURRING IN THE NEIGHBOURHOOD OP PLYMOUTH. 23 



habit of lying on one side may have brought about a superficial 

 similarity in fishes originally derived from distinct families. I hope 

 to decide this question by a careful comparison between soles and 

 other kinds of flat-fish in all points of adult structure. 



SOLEA VARIEQATA, 



I did not devote much attention to this species, as my time was 

 occupied with others; the following notes are therefore very meagre. 

 Until May 30th I had not been able to find any of this species in a 

 ripe condition. On that day the Laboratory fisherman brought me 

 a few ripe ova which he had taken from a fish on board a trawler 

 six miles south-east of the Eddystone. He had not been able to 

 get any milt. When I examined the ova they were all at the 

 bottom of the jar apparently dead, and all I could make out was the 

 size and a large group of numerous oil-globules, individually larger 

 than those of 8olea vulgaris. These all collected at the highest 

 point of the ovum when placed on a slide. The diameter was 1*36 

 mm. The appearance of the ovum is shown in fig. 14. 



On July 17th, I obtained from a tow-net worked by the 

 Laboratory fisherman from a mackerel boat south-east of the Eddy- 

 stone a peculiar kind of pelagic ovum which is shown in fig. 15. 

 This had a superficial layer of yolk-segments, like Solea vulgaris, but 

 the oil-globules, though rather numerous, were of rather large size, 

 and were scattered singly at nearly equal distances over the surface 

 of the yolk. The diameter measured 1'36 mm. Thus the size of 

 the ovum and of the individual oil-globules agreed closely with the 

 dimensions noticed in the unfertilized ovum of Sofea variegata. I 

 conclude provisionally that the ovum shown in fig. 15 belongs to 

 this species. Raffaele examined the ovarian eggs of only three 

 species, 8. iinioar, vulgaris and Kleinii, Impar is considered by Day 

 in his Fishes of Great Britain and Ireland as synonymous with 

 lascaris, which is Couch's lemon sole, and occurs occasionally on the 

 coast of Devonshire ; Kleinii occurs only in the Mediterranean. 

 Thus there is nothing to show that Solea variegata may not have 

 separate oil-globules ; and although in the dead unfertilized ovum I 

 observed them all in one group, this does not prove that they are 

 not in the later stages of the living egg fixed at a distance from one 

 another. Moreover, Raffaele describes and figures among his 

 undetermined species an ovum which agrees in all respects with that 

 shown in fig. 15 except that it is 1*4 mm. in diameter instead of 

 1*36. This difference may be due to the conditions of measurement 

 or to individual variation. Raffaele thinks his ovum belongs to 



