458 THE ZOOLOGIST. 
the one next to it; after that they are fairly evenly spaced, the 
spaces, however, decreasing as the size of the gill-rakers dwindle 
towards the end of the hypobranchial, the last two or three 
becoming small flat plates. The second and third branchial 
arches have tubercle gill-rakers on each side, those on the inner 
side being smaller than those on the outer; they are all covered 
with teeth. The inner side of the first and outer edge of the 
fourth arch also have toothed tubercles. The top of the second 
epibranchial has a small patch of cardiform teeth as part of the 

Fic. V.—XIPHIAS GLADIUS. 
upper pharyngeal teeth system, and below this on the third and 
fourth epibranchials is a large protruding patch with strong 
teeth on it, forming the bulk of the upper pharyngeal teeth. 
There is one of these patches at each side, and the distance 
between the upper and lower patches is rather more than is 
usually found in other fishes. The lower pharyngeal teeth do 
not lie flat on the floor of the mouth, as in most fishes, but are 
tilted up, forming an angle roughly of about 120°, with the 
floor just opposite the swallow. This inclination of the lower 
pharyngeal teeth gives, with the upper teeth, a very powerful 
