Henn: South American Pceciliid Fishes. 121 



like intromittent organ, contained 2.2 to 2.3 in the entire length. It is 



inserted forward of the anterior third of the entire length. Ventrals 



anterior to the origin of the anal, minute; rays not modified. Male 



elongate, greatest depth about 5 in length to base of caudal. Eigen- 



mann, loc. cit., p. 430, fig. 6, gives excellent figures of the male anal 



fins. 



First and second anal rays of the male, minute; third, fourth, and 



fifth greatly prolonged. In the normal folded position, these lie 



closely apposed, forming a simple needle-shaped organ. Distal 



part of third ray club-shaped, near the tip free from the fourth, which 



tapers evenly and bears dorsally a series of strong, retrorse hooks. 



These lie downward or enclose the folded organ. Fifth ray heavy and 



tubular, closely joined to the fourth. Other rays much shorter. 



Cnesterodon difi"ers from this genus in the presence of a long terminal 



hook. 



Key to the Species of Phalloptychus. 



a. D. 8; A. 9; V. 6; depth 4; vertical bands usually nine or fewer. 



I. eigenmanni Henn. 

 aa. D. 9; A. 10; V. 5; depth 3.5, vertical bands usually more than nine. 



2. januarius (Hensel). 



20. Phalloptychus eigenmanni Henn, sp. nov. (Plate XX, figs. 2 and 3.) 

 4665 C. M., tjrpe, female, 29 mm. 4666, C. M., paratypes, two 



males, 20-22 mm.; eight females, 25-30 mm. Alagoinhas, Rio 



Catu, Bahia. March 4, 1908. Haseman. 



D. 8; A. 9; P. 10; V. 6; head 4; equal to depth at origin of anal; 

 caudal peduncle 6 in length to base of caudal and 1.5 in head. Eye 

 3 in head; 2 in caudal peduncle and equal to the interorbital width. 

 Scales 27-29 in lateral series, 8 in transverse series. Snout short, 1.3 

 in eye; chin steep. 



Distance from tip of snout to origin of dorsal, slightly less than 

 distance from anal origin to tip of middle caudal rays. Dorsal origin 

 over last rays of anal. Pectorals as long as the head minus the snout; 

 ventrals just reaching the vent. Caudal elongate, rounded. 



A series of from seven to nine vertical bands of color adorn the sides. 

 The last two are often united to form a trident. Peritoneum silvery; 

 color-bands absent over the visceral cavity. 



This species differs from P. januarius (Hensel) in the more elongate 

 form, smaller dorsal and anal, larger ventrals, and the fewer color- 

 bands. 



Named in honor of my respected professor. Dr. C. H. Eigenmann. 



