102 VERTEBRATA. PISCES. 



ed, when the poor creature appeared the water around 

 him was dyed with blood. In this manner they con- 

 tinued tormenting and wounding him for many hours, 

 until we lost sight of him ; and I have no doubt they, 

 in the end, completed his destruction."* The spe- 

 cies thus alluded to is doubtless the X. Gladius, a 

 native of the Mediterranean and Atlantic, which 

 sometimes attains the length of fifteen feet. Its flesh 

 is said to be hard, but good and nourishing. 



Naucrates,^ the Pilot-fish. 



A single dorsal fin, before which, as well as before 

 the anal, there are a few free small spines, and a 

 ridge on the sides of the tail, are the distinctive marks 

 of this genus. The single species recognized (N. 

 Ductor) is well known to seamen from its constant 

 attendance on the White Shark, (Carcharias Vul- 

 garis,) to which it evidently acts, strange and unac- 

 countable as it undoubtedly is, as a guide to food. 

 Cuvier asserts, that "it follows ships to seize on what 

 may fall from them ; and as a similar habit is ob- 

 served in the Shark, it has been said that the former 

 acts as guide or pilot to the latter," but this is a very 

 summary mode of removing the difficulty. The 

 author of this work has had several opportunities 

 of observing the connexion, and never without ad- 

 miration and surprise. Though, during a long calm 

 in a voyage to the Gulf of Mexico, as well as 



* Memoirs of Capt. H. Crow, p. 11. 

 t N#i/xTjj, naukrates, a pilot. 



