232 



INDIANA UNIVERSITY 



Closely related to R. altipinna Fowler of the Chimbo-Chan Chan basin of 

 the Guayas system of Ecuador. R. altipinna is a much deeper and larger fish 

 occurring probably not higher than the type-locality below Bucay, at an alti- 

 tude of about seven or eight hundred feet. R. minor is a dwarf mountain 

 form from over 4,000 feet. 



R. minor is distinguished by its lesser depth, the relatively feeble den- 

 tition, more forward position of the dorsal and size. Scarcely any difference 

 in number of scales. In mature specimens of Rhoadsia the maxillary extends 

 to below the posterior margin of the eye. R. ininor is mature when 95 mm. is 

 attained and R. altipinna at 140 mm. A corresponding relation exists at all 

 stages in the development of the maxillary. Among specimens of 40 mm. 

 in R. minor the maxillary extends below the vertical from the anterior corner 

 of the orbit. In R. altipinna the maxillary is more slender and extends but 

 slightly beyond vertical from posterior nares. In specimens of 56 mm. R 

 minor has the maxillary reaching vertical from anterior third of eye; in R. 

 altipinna the maxillary reaches vertical from anterior corner of orbit. At 

 95 mm. R. minor is mature; R. altipinna has the maxillary reaching nearly 

 to the suture between the first and second suborbitals. 



''From small, crystalline brooks of the Rio Blanco at Mindo at an elevation 

 (Reiss and Stiibel) of 4,136 feet. Mindo consists of the large hacienda San 

 Vicente, situated in the extremely humid sub-tropical forests of the western 

 folds of Mt. Pichincha, draining to the Rio Esmeraldas. 



''A brillant little fish, locally kno\\Ti as 'doradillo' (little gilded one). 

 I also heard of this little jewel, when in the hot dry valley of the Chota of 

 Northern Ecuador, near the irrigated sugar plantation 'Cabuyal,' here at 

 an elevation of some 4,900 feet." 



Hemigrammus barrigonae Eigenmann and Henn, sp. nov. 



Type, 41 mm., 13423 I. U. M.; paratypes 65 specimens 25-43 mm., 13424 I. 

 U. M. Barrigona, Rio Meta. Coll. Manuel Gonzales. 



Head 4; depth 2.6-3; depth of caudal peduncle 9-10; D. 11; A 24-25. 

 Scales 33-35 in a longitudinal series, about 11 in a transverse series. De- 

 velopment of scales with lateral line pores extremely variable and not even 

 equal on both sides of the same specimen. Usually a continuous series of 

 at least 14 scales with pores, thence lateral line discontinuous; pore usually 

 developed on last scale in the series. One specimen has the lateral line 16+ 

 3-1-1+11+2, (the underlined numerals represent scales with pores). Another 

 has 17+6+2+4+2+3. A specimen of 41 mm. has the lateral line 17+14+2 

 on the left side and 16+18+1 on the right side. Of others, one, 34 mm. has 

 respectively 24+8+3 and 20+8+7; one, 37 mm. has 15+19 and 16+18; and one, 

 42 mm., has 24+5+5 on the left and 24+7+3 on the right side. The lateral 

 line is developed on the seventh transverse series of scales. Scales in the 

 type are 6-16+18+1-4. Eye 2.6 in head, about equal to or slightly greater 

 than the interorbital. 



Compressed, rather deep, caudal peduncle slender; predorsal area arched 

 or rounded with a variable median dorsal series of scales, from 9 to 12 (usually 

 10); preventral area rounded, with an ill-defined median series of about 12 

 large scales. Occipital process about 5 in the distance from its base to the 

 dorsal, bordered by three scales. Skull convex; fontanels moderately large; 

 second suborbital in contact with the preopercle behind. 



Mouth terminal; snout blunt, about one-half the eye; maxillary short, 



