FISHES OF THE PHILIPPINE ISLANDS AND ADJACENT SEAS 149 



jQsh known among seamen as the Pilot {Naucrates duct or.) This 

 fish, which is about a foot long, presents a handsome appearance, 

 being silvery blue with broad transverse bands of dark blue. Sea- 

 faring folk in general suppose that it guides the Shark to the prey in 

 the hope of gaining its share thereof, and this belief has been supple- 

 mented by all kinds of romantic additions. Cuvier, who discussed 

 the improbability of these fabulous narratives, was of the opinion 

 that the companionship of the Shark and the Pilot fish is merely 

 fortuitous, each of them following the vessel. But this is not the 

 case. The Pilot-fish really attends upon the Shark, but only to feed 

 upon its excrements, as a few writers, ancient and modern, have cor- 

 rectly stated. I have often had the opportunity on tropical seas of 

 carefully watching Sharks accompanied by one or two Pilot-fish, and 

 have always made the same observation. The Pilot-fish keeps close 

 to the body of the Shark, at the dorsel, pectoral, or ventral fins, but 

 now and then quits his post to take some floating object he has espied. 

 Apparently,.' however, lie seldom finds anything that ticldes his 

 palate, and soon returns to the Shark; but the moment the Shark 

 passes any excrementitious matter the Pilot promptly and eagerly 

 makes off to secure the prize, and then returns to its former station, 

 from which it refuses to be enticed for a long while, whereas, when 

 it is hungry, it readily swims after any small object thrown into 

 the water. I never succeeded in hooking a specimen. In the Bay 

 of Bengal I had good opportunity of observing that large turtles are 

 also attended by the same kind of Pilot-fish; and Suckmg -fishes 

 (Echeneis) accompany both Sharks and turtles, for the same reason 

 as the Pilot, but always adhere firmly to the body of their host, till 

 they see any morsel of food, when they vie with the Pilot-fish in 

 agility, and, their errand accomplished, immediately return to attach 

 themselves as before." (Sundevall.) 



ANALYSIS OF SPECIES » 



o'. IsoPLAGiODON. Seconcl dorsal smaller than anal. 

 5\ Second dorsal and anal origins opposite. 



&. Snout elongate limbata 



c^ Snout moderate, rather pointed. 



<P. Preoral length 1% in mouth width; gill openings twice deep as eye 



width brachyura 



<P. Preoral length greater than mouth width ; eye greater than half depth 



of gill openings macrura 



c*. Snout moderately rounded, narrow, shovel-shaped, not acute, longer than 



mouth width ; color bronze brass ahenea 



c*. Snout pointed before eyes, length less than mouth width- amblyrhynchos 



c\ Snout short, blunt, length less than mouth width stevensi 



v. Second dorsal origin behind anal origin; snout moderate, blunt, nostrils 

 about midleugth sorrah 



