6 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 9I 



teriorly, one above the upper lip at a point midway in the length of the 

 gape, one below the eye, and two behind the orbit. There is a linear 

 series of six small pores on the mandible below the lower lip, followed 

 by two on the subbranchial region. The lateral line originates midway 

 between the eye and gill-opening and continues to the hypural. There 

 are i66 pores in its course, the last 6 or 7 without external openings. 

 The eleventh above the pectoral base, twentieth above tip of pectoral, 

 and fifty-seventh above the vent. Vertical fins of medium height con- 

 fluent around the caudal. Color faded in alcohol to a light brownish, 

 the ventral surface lighter. Dorsal fin with a black margin, anal with 

 a black border posteriorly, pectoral pale. Surface of head and body 

 sprinkled with fine dark points, most noticeable on the branchial region, 

 about the eye, and at the corner of the mouth, where they form dark 

 shades. 



This species is very closely related to Congroniuraena mellissii 

 Giinther,' agreeing perfectly with Giinther's brief diagnosis of his 

 St. Helena specimen. However, a second example recorded and figured 

 from the type locality by Cunningham * shows that our fish disagrees 

 with that species in having a longer snout, smaller mouth, lower fins, 

 and a very different gill-opening. It differs from Ariosoma balaerica 

 ( Delaroche ) * in the more anterior insertion of the dorsal fin, longer 

 tail, and in the much narrower isthmus, which in our specimen is much 

 narrower than in any other congrid eel the writer has seen. 



Measurements of the three specimens in millimeters are given below. 

 Under each measurement three figures are given, referring, in order, 

 to the three specimens. 



Total length 475. 414, 345 ; head 80, 74, 62 ; snout to vent 202, 177, 

 145; vent to end of tail 274, 236, 195; orbit length including adipose 

 eyelid 15.5, 15, 12; snout 16, 15, 12; maxillary 21.5, 19, 18; mandible 

 20, 17.5, 16.5 ; pectoral fin 28, 23, 20; branchial opening 13, 11, 9; tip 

 of snout to dorsal origin 78, Jt^, 62 ; isthmus to vent 120, 104, 85 ; depth 

 of head at end of its second third 30, 27, 22 ; width of head at same 

 point 23.7, 22, 18; depth of body at vent 25, 22, 18; width of body at 

 vent 17.5, 16, 13; width of isthmus 6.5, 5, 4.7; width of interorbital 

 10, 9, 7.3; eye, vertical diameter 10, 9, 8.5; height dorsal fin 7, 6, 4; 

 longest ray of dorsal fin 11, 10, 8; height anal fin 5, 4, 4; pores in 

 lateral fine 160-)- 6, 1604-8, 160 + 7. 



' Cat. Fish. British Mus., vol. 8, p. 42, 1870. 

 *Proc. Zool. Soc. London. 1910, p. 93, pi. 4. fiff- i. 



•See Norman (Ann. Mag. Nat. Hist., ser. 9, vol. 15, p. 314, 1925), for probable 

 differences between balaerica and the American opisthophthalma. 



