FISHERY Bl'LLETIN VOL 



over teeth at midlength of 1.0 mm. The teeth are 

 strongly heterodont and are rather definitely 

 aligned, especially marginally, in rows. The teeth 

 along the posterior margin number 41; those near 

 the middle on each side are in nearly a single 

 series alternating in proximity to the edge, 

 whereas those toward either end tend to be ar- 

 ranged in oblique, separate rows of 2-4 teeth. All of 

 these teeth are essentially erect, fairly stout, and 

 pointed, with the tips not bent backward. The 

 teeth along the two margins tend to form a rather 

 even row; they are all sharply pointed, rather 

 strongly bent backward, tend to flare outward, and 

 are, in general, especially forward, larger and 

 stronger than the teeth within; toward the an- 

 terioi' angles of the arch the marginal teeth tend to 

 have a rather weak lobe on each side below the tip, 

 and thus intergrade toward the median teeth. In 

 the anterior half of the length of the arch the whole 

 set of teeth grade from nearly triserial to unise- 

 rial. with only the very strong marginal teeth of 

 each side occupying much of this space. After some 

 intergradation, both anteriorly and laterally, the 

 teeth occupying the major triangular part of the 

 arch are dilated and bear on each side, well below 

 the tip, a lobe or a cusp; they are strongly bent 

 backward. Anteriorly the margins of the arch are 

 rather strongly concave. 



The length of each dental surface of the second 

 pair is 8.9 mm; the maximum width of each, near 

 the posterior end, is 2.7 mm. The teeth are ar- 

 ranged on each bone in about 16 rather regular 

 rows extending from near the midline outward 

 and backward in a weak curve. Teeth of reduced 

 size, but otherwise similar, also curved, are found 

 on a fimbriate pad immediately behind each bone. 

 All of the teeth are bent backward. A number of 

 teeth at the anterior end are simply conical, and 

 especially strong. Virtually all of the other teeth, 

 including those along the median and lateral 

 edges, are tricuspid, with the median cusp very 

 much stronger than the lateral pair, which arise 

 well below the tip. The two bones are narrowly 

 separated and a strongly fimbriate compressed 

 membranous ridge intervenes, grading both for- 

 ward and backward into several papillate rows. 



The length of each bone of the third pair is 5.8 

 mm, the width of each 1.9 mm. The small teeth 

 ari.se from a strongly papillate surface. They are 

 directed mesiad and are strongest on the median 

 margin, but definitely weakening laterally. They 

 are all conical, without any trace of marginal en- 

 largement. 



Ncinichlhys siniulans, 85.0 mm SL, 68.0 mm BL. 

 from the central South Atlantic. 24 02.5' S. 

 15 32.0' W (SIO 6.3-5461. The lower pharyngeal 

 measures 1.9  3.3 mm. As in Elassichthys. but 

 contrasting with the two large species, the arch is 

 less attenuate forward and the posterior border is 

 definitely convex instead of being slightly con- 

 cave. There is no definitive alignment of the teeth. 

 and a band about three or four teeth wide extends 

 virtually to the fi-ont tip. The teeth rather regu- 

 larly and strongly increase in size backward. 

 About 20 teeth in one very irregular row. or in twn 

 rows, occur along the posterior margin; these are 

 essentially erect, mostly very large, relatively, 

 and show barely a trace of the lateral enlarge- 

 ments. Toward the front end the teeth are conical 

 and less curved backward than the following teeth 

 (excluding the posterior marginal ones). Most of 

 the other teeth bear on each margin, well below 

 the tip. either a lateral swelling or a definite cusp. 



Each second pharyngeal measui-es 0.9 « 3.1 

 mm. with the greatest width well behind the mid- 

 dle. The teeth are scattered without definite 

 alignment. Those in the narrow front end of the 

 arch and those along the outer margin are conical 

 or nearly so. with the tips bent backward, .some- 

 what as in the other species. The remaining teeth, 

 however, are vastly different, actually submolar. 

 These rather lobular teeth seem to have been built 

 on a much swollen and rounded version of the 

 corresponding teeth in the other series, sometimes 

 showing a trace of the lateral enlargements or 

 cusps; but essentially they are irregularly round- 

 ed domes, but grading forward, outward, and 

 backward into the more conventional, weakly 

 tricuspid type. 



Each third pharyngeal measures approximately 

 0.6 X 1.6 mm. The arch is widest behind the mid- 

 dle. The teeth are rather hidden in the papillae 

 and all are simply conic, weakly curved backward. 

 They are quite strong along the inner margin but 

 grade into extremely minute ones on the outer 

 margin. 



DISTRIBUTION 



The distributions of the .scomberesocid fishes 

 have been depicted by various Russian and 

 Japanese authors. The Russian data are sum- 

 marized by Parin (1968a. b, 1969a). Parin (1968a, 

 b) received from us many of his data on "Scom- 

 heresox sp" ( = Nanichthys simtilans) and on Col- 

 nlahis ndncetus ( = Elassichthvsndoretus). Dudnik 



550 



