74 



Part III. — Twenty-fourth Annual Report 



They are broadly ovate, and the margins are obscurely crenulated ; they 

 are also moderately thin, and at the time they were removed from the 

 fish the concentric growth-lines were very distinct. 



Pleuronectes limajida, Linn. The Dab. PI. ii. b., figs. 28 and 29 ; pi. 

 iii. a., figs. 27-31. 



The earstones represented by rigs. 27 and 28, pi. iii. a., are from dabs 

 of moderate size (8 to 9 inches long), but their exact length was not 

 recorded. They have a tolerable resemblance to the earstones of young 

 halibut, represented by figs. 2 to 5 on the same plate (pi. iii. a.). They 

 measure about 5mm. in length by about 3mm. in depth. Figs. 29 to 30 

 represent the earstones of fishes measuring 7| inches, 5| inches, and 4| 

 inches long, while the earstones themselves measure about 4'5mm., 

 3*5mm., and 3mm. respectively, their width being about two-thirds of 

 the length. 



Pleuronectes cynoglossus, Linn. The Witch Sole. PI. i. b., figs. 

 26-29 ; pi. iii. a., figs. 22-26 ; pi. iv., fig. 30. 



The witch sole has earstones which differ very distinctly in shape from 

 all the other species of Pleuronectes referred to here. They are large in 

 proportion to the size of the fish, very flat, and nearly circular in outline, 

 and it is in this latter respect that they differ so distinctly from the 

 other species. 



The largest of the witch soles mentioned here measured 16 inches in 

 length, and its earstones (pi. iii. a., fig. 22) were fully 8mm. across their 

 longest diameter by about 7"5mm. across the narrowest part. The lower 

 margin is nearly straight, but otherwise the outline is almost circular. 

 The longest diameter of these earstones is about one-fiftieth part of the 

 entire length of the fish. The other specimens whose earstones are 

 represented here were of various sizes, and all of them smaller than the 

 one referred to above. The length of the different specimens and the 

 size of their earstones are given in the annexed Table. 



Figure on the 

 Plate. 



Length of the Fish. 



Earstones. 



Length. 



Width. 



26 (pi. i. b. ) 



27 „ 



28 „ 

 29 



23 (pi. iii. a. 



24 „ 



25 „ 

 26 



170mm. 

 165mm. 

 160mm. 

 153mm. 

 12 inches. 



Hi 



10* „ 



n „ 



3 , 5mm. 



3 •5mm. 



3'5mm. 



3 -2mm. 



5'omin. 

 ( One 5 '5mm. and 

 \ one 5'Omm. 



5'Oram. 



4'3mm. 



3.5mm. 

 3 "2mm. 

 3 -3mm. 



3 0mm. fully. 

 5 0mm. 



One 5 , 0mm. and 

 one 4 "7mm. 



4 *5mm. 

 4 '2mm. 



It will be observed that the earstones represented by fig. 26 (pi. iii. a.) 

 have about the same proportion to the length of the fish as that of the 

 larger examples specially referred to, while a slight variation is observ- 

 able in the length of the earstones of the smaller fishes. 



