616 PROCEEDINGS OF THE NATIONAL MUSEUM. vol. xxvii. 



opercle has a strengthening ridge developed on its inner surface extend- 

 ing back from its articulation with the hyomandibular. The lower 

 jaw has a very small angular. There is no space between the upper 

 edge of the articular and the upper limb of the dentary. The maxil- 

 lary has a large thin supplemental bone on its upper edge near the pos- 

 terior end. The premaxillary is long and slender and reaches nearly 

 to the end of the maxillary. The suborbital ring has a very long nar- 

 row shelf which tapers nearly to each end of it but does not extend on 

 the preorbital. On its outer side there is a deep channel. 



HYOin ARCH. 



The interhyal is rather long and is attached by a ligament at its 

 lower end to the upper part of the interopercle as well as to the sym- 

 plectic at its upper end. There is a channel running the length of the 

 ceratohyal and extending on the epih3'al. The urohj^al is simple and 

 flat without lateral wings or ridges. The hj^poh^^als are j^aired on each 

 side as usual. There are four unmodifled branchiostegal rays; one 

 and a half on the epihyal, and two and a half on the ceratoh3'al. On 

 the lower hypohyal are too small, curved rays of bone, one fitting 

 closely against and on the inner side of the other, so that it is nearly 

 covered when viewed from the side. The hyoid barbel springs from 

 a point just posterior to the base of these, and around its slightly 

 swollen base they curve and are attached. To the outer side of the 

 barbel is attached a third bone, xQvy thin and flat, which also springs 

 from the h^^pohj^al. These are doubtless modified branchiostegal rays, 

 so the entire number on each side is seven. 



PHARYNGEALS. 



The lower pharyngeals arc straight on their inner edges, and in 

 contact but are not united. There are two toothed superior pharyn- 

 geals. That of the second arch is long and narrow, that of the third 

 and fourth is large, ovate, and cut rather square behind. 



VERTEBRAL COLUMN AND THE APPENDAGES OF THE UNPAIRED FINS. 



Abdominal vertebra 12+ caudal 15+ hypural =28. The first ver- 

 tebra is not concave in front, but is modified to fit the unevenly con- 

 cave occipital condyle. It has a small pit near its center. The third 

 vertebra has the first parapophysis developed. The parapophyses 

 grow more downward posteriorh", and the last two are connected near 

 their bases with their fellows of the opposite side. The first two 

 vertebrae, as usual in the spin}^ rayed fishes have only small single 

 rays more in line with the intermusculars than with the ribs. The 

 row of intermusculars follows along the parapophyses, a little above 

 the base of the ribs to the last abdominal vertebra, where it arches 

 upward and runs along the sides of the neuropophyses nearly to 



