118 PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM. 



POLYNEMIDiE. 



52. Polyiiemus virginicus Linnseus. ( Polynemus jylumieri (Lac^pecle).) 



Two very young specimens taken in the surf. There is not much 

 doubt that this is the species intended by Linnaeus, in his description of 

 Polynemiis virginicus, although the character '■'■cmida integra'''' does not 

 apply to any Polynemus. 



Silvery, back and upper part of sides dotted with blackish ; lower lobe 

 of caudal and tips of dorsals partly black ; pectoral pale ; pectoral 

 filaments reaching a little past vent. 



In older specimens from Cuba the speckled coloration disappears ; 

 the pectoral becomes largely black, and the other fins grow more dusky, 

 the markings on the caudal becoming more difiuse. 



ECHENEIDID^. 



53. Echeneis nauciates Linu.Tus. Sucking-fisli ; Sucker. 



Very common. Found attached to sharks, groupers, or any other 

 large fish, without regard to species. Few large sharks are without 

 them. Often caught with hook and line from the wharf, where they 

 frequently forsake their host to take the bait. 



TRICHIURIDiE. 



54. Trichiurus lepturus Linnseus. Silver-fish. 



One large specimen taken; more abundant in summer. 



XIPHIIDiE. 



55. Histiophorus americanus Cuv. & Yal. Spike-fish. 



(? Histiophorus gracilirosiris and ? H. andpUirostris C. &. V., VIII, 1831, 308, 309. 

 f Makaira nigricans Lac6pede, IV, 688, 1803.) 



One large specimen taken with trolling hook. As no description has 

 yet been published of an American Histiophorns, I give the following 

 notes on this specimen, the skin of which is preserved : 



Bluish-black, paler below ; dorsal dusky-bluish ; its membranes with 

 many almost perfectly round black (not blue) spots, which are from 

 one-third to one-fourth diameter of orbit. 



Snout from eye 2f times length of rest of head. Lower jaw 2^ in 

 head. Front of eye nearly midway between tip of lower jaw and edge 

 of oj)ercle. Interorbital space broad, fiattish. If in postorbital part of 

 head. Maxillary reaching to slightly beyond eye, which iu 3^ in pos- 

 torbital part of head and 10 times in length of snout. Sword narrow, 

 regularly tapering, depressed, its upper and lower surfaces rounded, 

 less rough than the blunt edges. Sword nearly twice as broad as deep 

 for its entire length. Breadth of sword at a point midwaj' between 

 its tip and the front of eye contained twenty-five times in its length 

 from the eye. Longest dorsal spine three-fourths length of head. Ven- 

 trals, If in head. Pectorals, 2f ; caudal lobes, IJ. 



