40. MVLKTES. 375 



^ncluded), the length of the head one-fifth; operculum about thrice 

 limb bvT fS^' i^7^^^tf.ri»g s'^Parated from the pra^opercular 



h^ fin^vnl ^ f"^'^. '^'''- ^^P°«^ ^ «^«rt, rayed; noue of 

 tuc tin-rays are prolonged. 



Brazil. 



7. Myletes orbignyanus. 



0«'. (§• Val. xxii. p. 220. 



D. 14. A. 32. 



filo^of f^'^T^i' '^*'' *^' l"^'' P'*^^^ subsemicircular ; upper pro- 

 witllfl'l ^'r'^l/^'^^^^y^, ^b«^e the eyes. Anal fiu not very high, 

 Mithout lobe in the midcUe. Scales very smaU. (Vnl) 

 rarana. v •/ 



Myletes duriventris 



letragonoptenis am-eus, Spix, Pise. Bras. tab. 31. 

 Myletes aiu'eus, At/ass. in Sjnx, Pi.sc. Bras. p. 74. 



D.15. A. 33. V. 8. L. lat.150. 



f.^I"^ ^".t^*. °^.^'''', ^""^^ '"* contained once and five-sixths in the 

 total leng h (with the caudal), the length of the head five times. 

 Abdominal serrature composed of thirty-nine simple spinous plates. 

 Dorsal rays not prolonged ; the rays towards the posterior third of 



idinZ fi w ^Ti.""-*^" *^^ °thers, forming an obtuse lobe. 

 Adipose fin short. The infraorbital ring is separated from the pr^- 

 opercular hmb by a strip of naked skin. ^ 



Brazil. 



9. Myletes bidens. 



'Spix, PLsc. liras. p. 75. tab. 32. 



D. lG-17. A. 26-28. V. 9. L. lat. 95. 

 The height of the body is contained once and three-fourths in the 

 total length (without caudal), the length of the head thrice and one- 

 sixth ; operculum thrice as high as long. Abdominal serrature com- 

 posed ot fifty-four spinous plates. Adipose fin very short The 

 outer profilesof the dorsal and anal fins convex. Coloration uniform 

 JNorthern Brazil. 



«. Half-grown. From the Collection of the Zoological Society. 



1 0. Myletes ellipticus. 



D. 27-29. A. 39. V. 7. 



The height of the body is contained once and three-fifths in the 



total length (without caudal), the length of the head thrice and 



onc-third or thrice and two-thirds. The u])por and lower T)ro- 



Wes arc neariy equally curved, the outlines of the bodv formin- an 



