on the Obliquity of Flounders. 371 



which its nervous and vascular connexions passed being indi- 

 cated in the mature skull by the unsymmetrical posterior half 

 of the articulating process of the right prefrontal, the eye having 

 maintained its normal relation to its associated bone (the right 

 frontal) throughout. 



The term " migration " of the eye is, of course, used in a 

 somewhat metaphorical sense. The eye changes little in actual 

 position. With the growth of the fish the associated parts are, 

 as it were, developed past it, producing this singular obliquity. 



Nothing can be more startling than the effect produced by the 

 changes in the position of the eye in these young Flounders. 

 We were kindly introduced last summer to the charming little 

 " Plagusise " by Prof. Steenstrup in his most instructive museum. 

 At first symmetrical miniature "jauues-dorees ;" next the right 

 eye becoming depressed inwards, and a strange little button-hole 

 appearing opposite it on the eye side, giving singularly the 

 effect of a Flounder with three eyes ; the eye slipping into the 

 button-hole, and finally all trace of its former socket becoming 

 gradually obliterated. Still, notwithstanding the wonderful 

 appearance of this migration, if our view be correct, but little 

 violence is done to the relations of the parts. The eye was 

 always under the skin, and it merely passes in its course beneath 

 a baud of opake integument to emerge under a second " pane " 

 of transparent skin which has been prepared for its reception. 



A valuable lesson may be drawn from Prof. Steenstrup's most 

 interesting observations upon " right " and " wrong " Flounders, 

 " double " Flounders, " albinos," and " negros." The dark 

 side of a Turbot is infinitely the more fully developed, the richer, 

 the fatter, the better in every way. According to modern usage, 

 if a Turbot be put on the table, this eye side is turned down- 

 wards; and the consequence is that usually, after the thin, 

 meagre blind side has been discussed in the dining-room, most 

 of the best of the fish is sent down to the servants' hall. It may 

 not be the cook's interest to remedy this, but surely it is her 

 mistress's ; for, under the present system, no lady, at all events, 

 can hope to reach the eye side of a Turbot. 



EXPLANATION OF PLATE XVIII. 



Fig. 1. Skull of the Turbot (Rhombus maximus): a, right prefrontal; 

 a', left prefrontal ; /, right frontal ; /', left frontal, 



Fig. 2. Heads of Plagusice (left and right sides) in three stages of meta- 

 morphosis. 



Fig. 3. Hippoglossus pinguis (Fabr.). 



Fig. 4. Hippoglossus vulgaris (Flem.). 



