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TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 



the absence, or at least great reduction in the size, of the 

 lower jaw. The upper jaw overhangs the mouth which 

 is reduced to a small crescentic slit on the lower side of 

 the head; both jaws are quite immovable. Whatever 

 food the fish obtained must have been of very small size. 

 There were no recognisable food remains in gut or 

 stomach. Nevertheless the fish appears to be healthy 

 and in good condition. 



Fig. 20. Trigla gurnardus. Natural size. 



Fig. 21 represents the normal suspensorium and jaw 

 apparatus of a grey gurnard, and it will be seen that we 

 have here the type which, with no essential variation, is 

 encountered among almost all teleostean fishes. In the 

 abnormal skull now before us (fig. 22), the parts of the 

 suspensorium and upper jaw are essentially as in the 

 normal skeleton. The palato-pterygoid arcade consists 

 of the same bones, and in the same relationships as in the 

 normal skull. So also with the maxilla and pre-maxilla. 

 The palato-pterygoid arcade is, it is true, shifted dorsally 



