BY W. MACLEAY, F.L.S. 6 



the gill covers extend quite to the symphysis of the lower 

 jaw, leaving a more or less open space on the chin, composed of 

 the integuments surrounding the extremity of the hyoid arch, and 

 forming the floor of the mouth. Of this general form there are 

 modifications in many families of fishes, but I have never before 

 known such a complete departure from the normal type as in the 

 present instance. 



Through the kindness of Mr. Haswell, who has made the 

 preparations and drawings for me, I am enabled to illustrate this 

 paper with two woodcuts, which will explain better than any 

 description the peculiarities of the fish. Fig. 1 represents the 



Fig. 1. 



under side of the head in the natural state, and Fig. 2 the same 

 with some of the integuments removed and showing the bones. 

 Mr. Haswell has also made for me a good preparation for 



