eigenmann: the cheirodontin^. 21 



well-developed. Mouth large; lower jaw heavy, its sides vertical; third suborbital 

 in contact with preopercle below and behind in the larger, with a narrow naked 

 border in the smaller specimens; three postorbitals covering the entire postorbital 

 area; no pseudo tympanum ; frontal fontanel very long; the frontals not in contact. 



3. Probolodus heterostomus Eigenmann. 

 Probolodus heterostomus Eigenmann, Ann. Carnegie Mus., Vol. VIII, 1911, p. 164, 



fig. 1; PL IV, fig. 1. (Campos on the Rio Parahyba; Iporanga on the Ribeira.) 



Range: Southeastern Brazil in coastal streams from the Rio Doce to the 

 Ribeira da Iguape. 



2973, C. M., type, 63 mm.; 2974, C. M., paratypes, three, 48-64 mm. Campos 

 on the Parahyba. June 13, 1908. Haseman. 



2975, C. M., paratypes, two, 78-81 mm. Iporanga on the Ribeira, Dec. 1, 1908. 

 Haseman. 



20910, M. C. Z., one, 77 mm. Rio Doce, between Linhares and Porto Souza, 

 Hartt and Copeland. Thayer Expedition. 



6882a, C. M., 45 mm. Sao Joao do Barra, Rio Parahyba. Haseman. 



6879a-b, C. M., two, 37 and 44 mm. Jacarehy, Rio Parahyba, July 15, 1908. 

 Haseman. 



6880a-g, C. M., seven, largest 35 .mm. Jacarehy, July 4, 1908. Haseman. 



Head 4-4.33; depth 2.66; D. 11; A 26-31; scales 8 or 9-45 to 53-7 to ven- 

 trals; eye 3, interorbital 2.5, snout 3.5 in the head in the type, 2.5, 3.2, 3.5 respec- 

 tively in the paratypes. 



Dorsal and ventral outlines nearly equally curved, without distinct humps or 

 depressions; ventral region rounded, the postventral area narrowly so. No regular 

 series of median scales in front of the ventrals. Predorsal area narrowly rounded, 

 with a regular median series of about twelve scales. Occipital process about five 

 times in the distance from its base to the dorsal, bordered by four or five scales 

 on each side; interorbital rounded, the frontal fontanel little more than half as 

 long as the parietal without the occipital groove. Snout sharp, the lower jaw 

 entering the profile when the mouth is closed; a distinct angle between maxillary 

 and premaxillary; maxillary not quite equal to length of eye; third suborbital 

 leaving a naked border around its entire lower edge. Gill-rakers 6 + 12. 



Scales everywhere regularly imbricate, except over the anal musculature; caudal 

 naked, a weak anal sheath of one series of scales along the base of the anterior rays; 

 each scale of the side, with several (maximum about eight) radial striae; axillary 

 scale of the ventrals well -developed. 



