CHARACID FISHES — WEITZMAN 



15 



7 radial grooves. Scales in lateral series 24 (23-26) ; perforated lateral 

 line scales 2 to 6 (usually 4 in population from Uruara Brook). Speci- 

 mens often damaged so heavily that scales impossible to count ac- 

 curately. In all instances, intact specimens from other localities 

 with only 4 to 6 perforated scales. Scales in median series anterior 

 to dorsal fin 10-11. Specimens from Uruara Brook with following 

 total vertebral counts: 6 specimens with 34; 19 with 35 vertebrae. 

 Specimens from Obidos: 3 specimens with 33, 31 specimens with 34 

 vertebrae, 8 specimens with 35 and 2 specimens with 36 vertebrae. 

 Most specimens from other localities wdth 35 vertebrae. Usually 

 18 to 20 precaudal vertebrae and 15 to 16 caudal vertebrae, always in 

 combination to produce total of 33 to 36 vertebrae. Counts of verte- 

 brae undoubtedly will prove useful in distinguishing and determining 

 subspecies. 



Figure 3. — Nannostomus heckfordi, female, SL 29.5 mm., SU 50261. 



Color in alcohol. — Preserved specimens from Belem, State of 

 Pard, Brazil (figs. 2 and 3) have the following color: Top of head 

 light to dark brown. Primary horizontal stripe extending from tip 

 of snout and tip of lower jaw across maxillary and first orbital bone 

 onto eye. Posterior to eye, primary stripe continuing to posterior 

 edge of opercular bone, but absent or extremely pale on fleshy oper- 

 cular flap. Beginning on cleithrum and underneath opercular flap, 

 primary horizontal stripe continuing posteriorly over lower midsides 

 onto caudal fin, its course reaching posterior root of anal fin, covering 

 entire lower half of caudal peduncle and continuing onto caudal fin 

 as a wedge with its apex at posterior junction of upper and lower 

 caudal fin lobes. In mature males primary horizontal stripe covering 

 entire foiu"th horizontal scale row and adjacent parts of third and 

 fifth scale rows. In mature females and immatm*e specimens of both 



