9G8 CONTRIBUTIONS TO NORTH AMERICAN ICHTHYOLOGY IV. 



Page 15G. Professor Hay (Proc. U. S. Nat. Mus. 1882) distinguishes 

 IlylHHjnathux <ir</yriti# from tlie less common //. iu:c!ia!is by the follow- 

 ing characters: 



. Eye small, shorter than snout; mouth small, horizontal, (lie lower jaw slur,-; and 

 included: suhorhitals broad, the anterior suborbital twice as King as wide: intes- 

 tinal canal 7 to 10 times length of body ................................ NUCHALIS. 



oa. E.M- large, longer than snout; mouth small, oblique, the jaws equal; suliorhi ai- 

 vciv narrow, the anterior thrice as long as broad; iniesiinal canal 44 to 71 limes 

 length of body ....................................................... AKGYKITIS. 



Page 1GO. After Hyborhynehus superciliosm add: 



8O (&). TIRODOJT Hay. 



(Hay, Proc. U. S. Nat. Mus. 1880: type Tirodon ainni'/i'mix Hay.) 



Pharyngeal teeth 2, 4-4, 2, compressed, not Looked, and with a broad 

 grinding surface; lower pharnygeal bones broad, sharply curved. 

 Otherwise as in Hyboyiwi'lius. (rztfui, to wear away; oy/u?, tooth.) 



194 (&). T. auiDtag^eaius Hay. 



Yellowish green, silvery below; upper parts dotted with black; these 

 dots forming posteriorly a dark streak along lateral line, and one along 

 cadi side of anal; tins pale. Form and appearance of Hyboynutlni* 

 I'l'tiyrii's. -laws thin, the lower slightly included; mouth small, rather 

 oblique, the maxillary not reaching front of eye; eye 'i in head, equal to 

 snout. Lateral line decurved, complete. Dorsal inserted slightly before 

 ventrals, a little nearer base of caudal than snout; anal small. Head 34; 

 I). 8; A. 7; scales 5-38-3. Teeth 2, 4-4, 2, formed as in llylognnthitx. 

 Intestinal canal 3J times length of body. L. 1 inches. Pearl 1 liver, 

 Mississippi. (Hay.} 



(Hay, Proc. U. S. Nat, Mus. 1882.) 



Page 201. Under Elops xn-arns the gular plate is about 3 times as 



lo:->l as hrninl. 



Page 2!>(i. In II _n>'' ! <nirtl>-:<s rlmlyhciitx the intcrorbital width is one- 

 ionrth the eye, not ik 1 limes." 



Pa-e 1".I7. ('<>fif/ >,i<'s concxi is identical with Corcgonm* tcillidintioni, 

 and may be suppressed. 



Page .">1.S. XiilrrU.tt'H iniri^i seems to be indistinguishable from Salrc- 

 iir.iit (njiui)iN<t. It may therefore be erased. 



