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TRANSACTIONS OF THE AMERICAN PHILOSOPHICAL SOCIETY 



Melanonus (Fig. 260) and Bregmaceros (Fig. 261) are highly specialized deep-water 

 anacanths. 



The macrurid skull (Fig. 262) is remarkable for its parchment-like texture, its many 

 enlarged fossae for mucous sacs, its enlarged ethmoid, forming a more or less projecting 



Bregmaceros atlanticus 



Fig. 261. Bregmaceros atlanticus. Sketch o{ skull from specimen prepared by Miss Gloria Hollister for Dr. William Beebe. 



rostrum often ending in three burrs. The premaxillae have retained large ascending pro- 

 cesses. This skull to me retains but little that is reminiscent of a scopeloid type, but seems 

 to be more suggestive of some secondarily spikeless derivative of the percoid group. 



Haplodoci (Toad-fishes) 



The skull of Opsanus tau (Fig. 263), representing the batrachoid fishes, presents extra- 

 ordinarily interesting patterns to the student of animal mechanisms. The forces of growth 

 and of evolution have favored the palato-pterygo-quadrate bars with their short conical 

 teeth, especially those in front, and the corresponding teeth on the dentary, with all their 

 supporting parts. The premaxillae are reduced practically to thin protrusile lips, bearing 

 little clusters of small pointed teeth at their front ends. The palato-pterygo-quadrate 

 bars as seen from above form a pair of stout, widely diverging legs, starting in front from 

 the broad, strongly braced vomer and abutting laterally and posteriorly on the laterally 



