70 PROCEEDINGS OF THE NATIONAL MUSEUM vol. 84 



midway between the eye and the lower angle of the preopercle. 

 Body and head, except snout and lower jaw, covered with minute 

 nonimbricate scales imbedded in the skin; scales of the dorsal region 

 following the course of the upper branches of the myomeric impres- 

 sions. Scales with 31 radiating striae. Origin of the dorsal fin 

 opposite, or a little before tip of appressed pectoral; the fin long and 

 low, joined to the caudal at base by membrane. Ventrals small, 

 closely approximated, situated below the branchial openings. Color 

 uniform pale olivaceous; the caudal fin dusky; other fins plain, 

 translucent. 



This species is represented by the type, 84 mm in standard length, 

 U.S.N.M. no. 84301, collected at Chame Point, Panama, by Robert 

 Tweedhe, and two paratypes, no. 82680, 68 and 96 mm, respectively, 

 from the same locaUty, taken March 8-14, 1913, by Mr. Tweedlie. 



This species is close to M. affinis Meek and Hildebrand and M. 

 longipinnis (Weymouth) but difters in the position of the vent, fewer 

 body vertebrae, and proportional measurements. 



MICRODESMUS MULTIKADIATUS Meek and Hildebrand 



Figure 12, b; Plate 2, Figure 8 



Microdesmus multiradiatus Meek and Hildebrand, Publ. Field Mus. Nat. 

 Hist., zool. ser., vol. 15, no. 249, p. 958, pi. 98, fig. 3, 1928 (Panama). 



Body very elongate, eel-shaped, the caudal notably longer than 

 rest of body. Head 9.7 to 12.8 in standard length; depth 20.2 to 

 28.0; predorsal 6.6 to 8.5; preanal 2.4 to 2.7; caudal without fin 1.6 

 to 1.7; preventral 9.7 to 11.6; base of ventrals to vent 3.2 to 3.6. 

 Snout 4.0 to 0.0 in length of head, measured from tip of lower jaw 

 to upper end of gill openings; interorbital 3.2 to 6.1. Dorsal 73 to 

 78, anal 57 to 61, pectoral 12, ventral 1-3. Eye small, high, super- 

 lateral; mouth comparatively large, little oblique, the maxillary to 

 anterior edge of eye. Lower jaw projecting with a small inconspicu- 

 ous fleshy tip. Lips very large, restricted laterally, the free flange 

 above and below very conspicuous, the two membranes joined 

 together around the posterior end of the gape; the free folds of the 

 hps do not extend around the mouth anteriorly^. Snout and lower 

 jaw with pronounced longitudinal swollen muscular ridges, those of 

 the lower jaw extending well back under the mandible. Anterior 

 nostril in a minute porelike opening at the oral end of the outer 

 frontal ridges. Posterior nostril in a small round opening on the 

 frontal ridge before and in front of the eye. Muscles of the jaws well 

 developed, the cheeks somewhat tumid. Teeth comparatively strong, 

 in two irregular series in the jaws, the lower jaw with three or four 

 small canines in the outer series, vomer and palatines tootliless. Gill 

 openings restricted laterally, adnate to the scapular region in front of 

 the base of the upper fourth pectoral ray, the aperture extending 



