1896. ] FISHES OF THU FAMILY GONORHYNCHID#. 503 
cranium is seen from above, but the only clearly distinguishable 
remains are those of the great pair of frontals (fr.). Some 
characteristic portions of the small mouth are observable forwards 
below; one of the maxille (mw«.), a dentary (d.), and apparently a 
fractured articulo-angular element (ag.) being distinct. The bone 
(x) above the maxilla may perhaps be part of the large preorbital 
cheek-plate seen. in Gonorhynchus (fig. 5). The right operculum 
(op.) and suboperculum (s.op.) are displaced upwards above the 
head, and the last-mentioned bone exhibits the four deep clefts 
in its hinder border. Remains probably of four large branchio- 
stegal rays (br.) occur below the head just in front of the rather 
obscure pectoral arch. 
The total number of vertebre cannot be definitely ascertained, 
but seems to be between 50 and 60. The centra resemble those 
of the American fish, thougk a little shorter in proportion to their 
depth: and the state of preservation of one specimen (Brit. Mus. 
no. P. 5884) suggests that each centrum was pierced mesially by 
the notochord. The delicate ribs are borne by stout processes 
from the centra, as noted by Agassiz, and as well shown in the 
specimen of which the head has been described. The neural 
spines are expanded in the anterior part of the abdominal region, 
as also shown in the same specimen and indicated by Agassiz 
in fig. 3 of his plate representing the species. The extremity of 
the vertebral column is formed precisely as described above in 
N. osculus, the lowermost expanded hemal spine at the base of 
the caudal fin being distinctly supported by the hinder border of 
the penultimate centrum; this, however, must be displaced for- 
wards, for both the penultimate and the antepenultimate centrum 
bears its own hemal arch, compiratively stout but not expanded. 
The fins appear to resemble those of V. osculus, but there are 
only eleven supports in the dorsal (clearly shown in Brit. Mus. 
no. 43436), the foremost with a wing-shaped expansion indicating 
its composite character. It is difficult to count the rays them- 
selves, the two halves of each being so loosely apposed that in 
crushing they frequently slip one behind the other. 
The scales are comparatively thick, and in their crushed state 
they rarely exhibit the posterior fringe of denticles. Careful 
examination of many specimens, however, shows that they pre- 
cisely resemble those of Gonorhynchus. A detached scale from 
the hinder end of the caudal region is represented of the natural 
size in Pl. XVIII. fig. 4. The radiating grooves in its deeply over- 
lapped portion are distinct, and the hinder fringe is partly restored 
from an adjoining scale. 
_ 3. NotoGonsus CUVIERI. 
(?) 1818. Anormurus macrolepidotus, H. D. de Blainville, Nouv. 
Dict. d'Hist. Nat. vol. xxvii. p. 374. 
1822. “Cyprin,” G. Cuvier, Oss. Foss. ed. 2, p. 346, pl. Ixxvii. 
fig. 15. 
1844. Sphenolepis cuvieri, L. Agassiz, Poiss. Foss. vol. v. pt, i. 
p. 13, pt. 1. p. 39, pl. xliv, figs, 1, 2 (? figs. 4-12, nee fig. 3). 
