74 Field Museum of Natural History — Zoology, Vol. X. 



length 3.3 to 3.5 in head; diameter of eye 3.4 to 3.9; snout 2.2 to 2.4; 

 preorbital ^.2 to 3.7, postorbital 2.5 to 2.7; pectoral i.i to 1.2; ventral 

 .7 to .9; base of anal .9 to 1.0. Caudal pedtincle 2.2 to 2.4; spinous 

 dorsal rather high, the 6th spine 1.9 to 2.2 in head; the last dorsal spine 

 1.5 to 1.6; last anal spine 1.5 to 1.7; gill rakers short, 9, dorsal, anal and 

 ventrals with their rays produced; caudal fin emarginate; soft dorsal 

 with scales on interradial membranes. 



Color olivaceous, sides w4th 6 or 7 indistinct cross bars. A lon- 

 gitudinal dark lateral band about as wide as eye, a large black spot on 

 side and a smaller one at base of caudal ; vertical fins usually with many 

 black spots. 



This species resembles C. balteatum but differs in havong a shorter 

 head and smaller eye, and longer dorsal and anal spines. 



Neetroplus fluviatilis sp. nov. 



Type No. 7585, F. M. N. H.; length 116 mm.; Costa Rica River near 

 Guapilis, Costa Rica. 



Head 2,-i', depth 2.6; D. XVII or XVIII, 9; A. VI, 6; scales 34. 



Body elongate, compressed, profile very convex; mouth small, sub- 

 inferior, the lower jaw the shorter, teeth compressed; preorbital very 

 deep, equaling the postorbital, 2.6 in head; eye 3.9; snout 2.2; inter- 

 orbital very convex ; scales on breast, nape, and along each side of dorsal 

 fin, very small; pectoral fins 1.4 in head; ventrals shghtly longer than 

 head; dorsal fin low, the last spine 2.2 in head, the 6th spine 3.1, last 

 anal spine 2.2; base of anal 1.2 in head; caudal peduncle 2.2 in head, gill 

 rakers very blimt, 3+6; caudal fin rounded. 



Color dark olivaceous, 6 or 7 faint dark bars on the sides. Known 

 from the type and one other specimen (105 mm.) from Costa Rica River 

 near Guapilis. 



Qobiesox costaricensis sp nov. 



Type No. 7577, F. M. N. H.; length 62 mm.; Zent, Costa Rica. 



Head 2.7; depth 5.6; D. 6; A. 4. 



Body broad, depressed anteriorly, teeth incisor, their edges entire; 

 dorsal and anal fins small, the latter under posterior half of the former. 

 Head broader than long, width of mouth about ^ width of head. 



Color olivaceous, with 4 or 5 darker bars on back extending on 

 sides. Caudal barred, a black spot at base of anterior rays of dorsal. 



The following are measurements (mm.) of the specimens obtained: 



