422 CONTRIBUTIONS TO NORTH AMERICAN ICHTHYOLOGY — IV. 
iu the tropical seas. Very close to the Scombridcc, from which group, 
as here understood, the TricUuridw differ chiefly iu the non differeuti- 
ation of the dorsal spines. {TricMuridce part; Giinther, 342-349.) 
*■ No caudal tin ; tail tapering to a point ; dorsal tin single ; no ventral tins. 
Tricuiurus, 212. 
212.— T5SICEIIIIRUS LinntBus. 
Hair tails. 
(icpfaras Artedi; Gill.) 
(LinnjEus, Syst. Nat. xii, 176t5: type Trichiunis lepiurtis L.) 
Body extremely elongate, band-like, the tail very slender, tapering to 
a fine point, without caudal fin. Head long, with a very wide mouth, 
the jaws armed with unequal and very strong teeth ; upper jaw with 
about four long, strongly compressed barbed teeth ; teeth on the pala- 
tines, none on the vomer. Lower jaw longest, preorbital covering cleft 
of mouth posteriorly. Dorsal flu single, low, occupying the whole of 
the back, the spines not distinguishable from the soft rays ; anal very 
long, its base more than half the length of the body ; composed of de- 
tached spines, which are very short, nearly hidden in the skin, the ante- 
rior directed backwards, the posterior forwards ; ventral fins wanting 
or reduced to small, scale-like appendages; pectorals small. No scales. 
Lateral line decurved, concurrent with the belly. Yertebne 39 -f 420. 
Color silvery. Voracious fishes of the high seas; reaching a consider- 
able size, {rpcxiov^ a little hair ; oupa^ tail.) 
a. Ventral tins entirely wanting in the adult. {Tricliiurus.) 
666. T. leptiirilS Linn. — Hair-iaU. 
Uniform brilliant silvery ; dorsal dark-edged. Snout long and pointed, 
about as long as pectoral; maxillary reaching nearly to pupil, concealed 
by i)reorbital. Head about iu length; depth about 1(3. Eye 2 in 
snout. D. 135; A. about 100. 'Warm seas, north to Virginia and 
Lower California. 
(Linn. Syst. Nat. xii; Giinther, ii, 346.) 
Family LXXIY.-SCOMBRID.E. 
, {The Maclcerels.) 
Body elongate, not much compressed, covered with minute cycloid 
scales, or else wholly naked; the scales anteriorly sometimes forming a 
corselet. Lateral line present, its course undulate. Head subconic, 
