292 MISCELLANEOUS OBJECTIONS TO THE [Chap. VIL 



is altered in shape, if the skin or muscles be perma- 

 nently contracted through disease or some accident. 

 With long-eared rabbits, if one ear lops forwards and 

 downwards, its weight drags forward all the bones of 

 the skull on the same side, of which I have given a 

 figure. Malm states that the newly-hatched young of 

 perches, salmon, and several other symmetrical fishes, 

 have the habit of occasionally resting on one side at the 

 bottom; and he has observed that they often then strain 

 their lower eyes so as to look upwards; and their skulls 

 are thus rendered rather crooked. These fishes, how- 

 ever, are soon able to hold themselves in a vertical posi- 

 tion, and no permanent effect is thus produced. With 

 the Pleuronectidse, on the other hand, the older they 

 grow the more habitually they rest on one side, owing 

 to the increasing flatness of their bodies, and a perma- 

 nent effect is thus produced on the form of the head, and 

 on the position of the eyes. Judging from analogy, the 

 tendency to distortion would no doubt be increased 

 through the principle of inheritance. Schiodte be- 

 lieves, in opposition to some other naturalisfs, that the 

 Pleuronectidse are not quite symmetrical even in the 

 embryo; and if this be so, we could understand how it 

 is that certain species, whilst young, habitually fall over 

 and rest on the left side, and other species on the right 

 side. Malm adds, in confirmation of the above view, 

 that the adult Trachypterus arcticus, which is not a mem- 

 ber of the Pleuronectidse, rests on its left side at the 

 bottom, and swims diagonally through the water; and in 

 this fish, the two sides of the head are said to be some- 

 what dissimilar. Our great authority on Fishes, Dr. 

 Glinther, concludes his abstract of Malm's paper, by 

 remarking that " the author gives a very simple expla- 



