PROCEEDINGS OF THE NATIONAL MUSEUM. 433 



(lill rakers absent. Preopercular margin free. Dorsal and anal fins 

 very long, the former commencing on the snout. Caudal jieduncle 

 extremely short, a low fin-fold joining dorsal and anal with rudimen- 

 tary caudal rays. Caudal lanceolate. Yentrals unsymmetrical, the left 

 slightly more anteriorly placed, inserted on the ridge of the abdomen, 

 its membrane leading to base of first anal ray. Vent displaced well to 

 tlie right side of the ridge slightly in advance of front of anal, a small 

 pai)illa (genital papilla?) occupying a corresponding position to the left 

 of the ridge. Scales excessively fine. Lateral line single, conspicuous, 

 continued on to the caudal fin; with a short, low anterior arch. 



PELECAr^ICHTHYS CRUMENALIS, new species. 

 (Plate XLVII.) 



Head (horizontal length) 4^ to 4i (5^ in smallest specimen); depth 

 3^ to of (4 in smallest); dorsal 121; anal S^S; jtectorals 13 or 14; ven- 

 trals of both sides with 6 rays; about 230 to 240 pores in the course of 

 the lateral line. 



Body slender, excessively compressed, tai)ering slowly and uniformly 

 toward tail, the two outlines very weakly arched for the greater part 

 of their extent. Anterior outline of head strongly decurved, the phys- 

 iognomy resembling that of GUjpiocephalus. Bases of dorsal and anal 

 fins wide, translucent, sharply marked oft' from rest of body, constitut- 

 ing together half the greatest depth of body. Abdomen very short. 



Head very obliquely placed, the eyes closely approximated near the 

 upper anterior profile, the cheeks imrrow, oblique, the upper limb of 

 preopercle nearly horizontal, the lower limb nearly vertical. Mandible 

 extending beyond premaxillaries for over one-fourth its length. The 

 rami are so articulated as to permit a slight inward and outward rota- 

 tion on their long axes, in addition to other movements. The gular 

 membrane is large and loose, falling into folds when the jaws are closed. 

 The entire mechanism of the lower jaw seems adai)ted to seizing food 

 between the rami, and forcing it down between and below them. Teeth 

 in both jaws in a somewhat uneven single series, those in mandible 

 largest, smaller teeth irregularly alternating with the larger ones in 

 both jaws. Posterior third of both jaws toothless. Palate smooth. 

 Anterior nostril with an overarching flap or short tube. Posterior 

 nostril without tube. 



Eyes elliptical, nearly even, long axis of lower eye very obliijue. 

 Obliipie diameter of upper orbit 3^ in head; the snout short, five- 

 sevenths diameter of upper eye. Interorbital space narrow, grooved, 

 ^fi-j width one-fifth diameter of upper eye. 



..^orsal fin beginning above anterior nostril, the first few rays slightly 

 -isiilaced toward the blind side. Pectorals narrow, pointed, about If 

 in length of head, that of blind side apparently shorter. Caudal lan- 

 ceolate in a young specimen (mutilated in adult), the middle rays IJ in 

 head. 



Proc. is. M. vol. xix 28 



