Jordan and Evermann. Fishes of North America. 61 



Pri*t;.< }>< < tiiHitii.*, LATHAM, Traus. Linn. Soc., n, 278, 1794, "in the ocean." 



Pristis ,/>-<tnnlsa, BLOCK & SCHNEIDEU, Syst. Iclithyol., 352, 1801, (after Parra), Havana. 



IWi* i><;'t;,t,,tiix, GfNTiiER, Cat., vin, 437, 1870. 



:;;-tin<Hn.<, JouDAX & GILBERT, Synopsis, 875, 1883. 



Pristis >H/.ss/ss/y^)jVs/.s, KAFINESQUE, Ich. Oh., 80, 1820, lower Mississippi. 

 Print is i,ir.,l,i<l,>n, DUMERIL, Elasinobranches, 476, pi. 9, fig. 4, 1870, Cayenne. 

 Pristis ncntin mi riii, IMPERIL, 7. c., 479, 1870, Martinique. 

 /VtWf's otrtj, DUMKIUL, ?. c. ,479, 1870, locality unknown. 



Family XXIII. RHINOBATIDJE. 

 (THE GUITAR FISHES.) 



Shark-like rays. Trunk gradually passing into the long and strong 

 tail, which is provided with 2 well-developed dorsal fins, a caudal tin 

 and a conspicuous dermal fold on each side ; disk not very broad, the 

 rayed portion of the pectoral fins not being continued to the snout ; no 

 conspicuous spines, the skin being nearly smooth ; no electric organs. 

 Genera about 5; species about 20; inhabiting warm seas, distinguished 

 from the RAJID.E chiefly by the fact that the eggs are hatched within 

 the body. The typical species are also much more elongated in form. 

 (RiiiNOBATiD/E, Giinther, Cat., vni, 440-448.) 



a. First dorsal much behind the ventrals; anterior nasal valves not confluent. 



b. Disk subtriangular or rhombic; the snout more or less produced; skin covered with 

 fine shagreen, usually with somewhat larger spines on the back of tail. 



RHINOBATUS, 45. 



bb. Disk rhombic, the snout less produced; nasal valves dilated, extending on the space 



between nostrils; body covered with irregular tubercles and prickles instead of 



shagreen. ZAPTKRYX, 46. 



bbb. Disk broad, rounded in front; nasal valves broad; body covered with shagreen, with 



stout spines on back and tail; labial fold well developed. PLATYHHINOIDIS, 47. 



45. RHINOBATUS, Bloch & Schneider. 

 (GUITAR FISHES.) 



hliinohatus, BLOCH & SCHNEIDER, Syst. Ichth., 353, 1801, (rhinobatus). 

 Ltiolxitus, RAFINESQUE, Caratteri, 16, 1810, (panduratus). 



Syrrhina, MI'LLER & HENLE, Plagiostomen, 113, 1838, (columnse = panduratus). 

 GlaucobteyHs, BONAPARTE, Catologo Metodico, 14, 1846, (rhinobatus). 



Body depressed, gradually passing into the tail. Cranial cartilage pro- 

 duced into a long rostral process, the space between the process and the 

 pectoral fin being filled by membrane ; spiracles wide, behind the eye ; 

 nostrils oblique, wide; anterior valves not confluent; teeth obtuse, with 

 an indistinct transverse ridge. Dorsal fins without spine; both far be- 

 hind the ventral fins ; caudal fin without lower lobe. Claspers slender 

 and pointed. Species numerous in warm seas, varying considerably as to 

 the form of the snout ; those with the snout shortened and the nasal 

 valves broader constituting the subgenus Leiobatus, or Syrrhina. (pivr/, 

 a shark; 0drof, a skate.) 

 BH i NO BAT us: 

 a. Nasal valves not extending on the space between the nostrils; disk subtriangular, the snout 



slender and pointed. 

 b. Spiracle with two folds. 



c. Skin abov<! every where closely freckled with whitish; ridges of rostral cartilage close 

 together, narrowly separated at base. LENTIQINOSUS, 81. 



