514 BULLETIN 100, UNITED STATES NATIONAL MUSEUM. 



extends backward from the occipital scute. The scales between the 

 occipital and postorbital ridges are reduced in size, excepting those 

 in the median series; a strong scute, pointed posteriorly and armed 

 with several spinules, is present near the origin of the lateral line. 

 The nasal fossa has a few scales in its anteroventral angle. The 

 underside of the head is completely naked. Six branchiostegals; free 

 fold of gill-membranes very narrow. 



A ventral fossa about as long as the pupil and covered by thin 

 and nearly smooth scales is located before the ventral fins. The 

 usual gland-like organ which this fossa covers shows through the 

 transparent scales. It is flat on its punctulate, yellowish outer sur- 

 face, and black on its thick, rounded anterior edge and arched dorsal 

 surface; it extends backward as a strand of glandlike substance, 

 surrounded by a black membrane, to its black posterior dilation, 

 which, located just before the anus, is covered by a small area in 

 which the scales are thin. 



In the sensory cavity lying in advance of the lateral line there are 

 developed small neuromastic bones, like those described in some de- 

 tail for C oelorhynchus argentatus (p. 434). 



Eleven pyloric caeca (one specimen examined). 



Table of measurements in hundredths of length to anus. 



Coelorhynchus 

 acuthostris. 



Coelorhynchus gladius. 



A Ibatross station 



Total length in mm 



Length to anus in mm 



Length of head 



Length of orbit 



Postorbital length of head 



Width of interorbital 



Width of suborbital 



Orbit to preopercle 



Length of snout: 



Preocular 



Preoral 



Width of snout: 



At base 



At end of ethmoid portion of infraorbital ridge. . , 



Length of terminal rostral plate 



Length of upper jaw 



Length of barbel 



Depth of body below origin of first dorsal 



Depth of body at twice length of head behind tip of 



snout 



Width of body across pectoral bases 



Width of body at twice length of head behind tip of 



snout 



Anus to ventral 



Ventral to isthmus 



Height of second dorsal spine 



Length of first dorsal base 



Length of first ray of second dorsal 



Length of interdo'rsal space 



Length of pectoral 



Length of outer ventral ray 



Length of second ventral ray 



Fin rays: 



First dorsal 



Pectorals 



Ventrals 



Tyje. 

 5418 

 205 



87.5 



72 



16.5 



21.5 



15 

 9 



23 



35 

 31 



23 

 17.5 

 10.5 

 15 

 4 

 33 



12 

 23 



4 

 24 

 23 

 25 

 11.5 



4 

 10 



21.5 

 23 

 15 



II, S 

 16-15 



Paratype 



5417 



190 



81 



74 



17 



22 



16.5 



9 



23 



37 

 31 



25 

 19 



10.5 

 15 

 4 

 35 



10 

 22 



3.5 

 21.5 

 21 

 22 

 10.5 



4 



8 

 25 

 21 

 15 



2 11,8 



14-13 



1237 

 96 

 70 



14.5 

 19 



J3.5 

 7.5 

 19 



36.5 

 33 



21 



15.5 

 13.5 

 13.5 

 5 

 27 



16 

 26 



10 

 26 

 17 

 33 

 12 



9 



8 

 26.5 

 24 

 16.5 



11,9 

 18-17 



157- 

 65 

 72 

 16 

 19 

 13. 

 8 

 19 



39 

 36 



22 

 18 

 16 



Paratype. 

 3472 

 57 



23.5 

 70 

 22 

 20 

 16 



22 



31 

 27 



27 

 24 



1 Pseudocaudal developed. 2 First dorsal rays II, 8 in each of the four specimens. 



(acutirostris, in reference to the sharply acuminate snout.) 



