MACEOSEMIIDJE. 
187 
Length of head with opercular apparatus considerably exceeding 
the maximum depth of the trunk and equalling half its length to 
the base of the caudal tin; width of caudal pedicle somewhat less 
than half the maximum depth of the trunk, which tapers gradually 
from a point close to the occiput. Dorsal fin arising at the end of 
the first quarter of the back, and its anterior portion twice as much 
extended as the hinder portion; the first comprising about 14 rays, 
very widely spaced and all shorter than those of the second portion, 
which are more closely arranged and only 10 in number. Anal fin, 
with large fulcra and about 6 rays, as deep as the second portion 
of the dorsal and arising slightly behind the origin of the latter. 
Scales very finely crenulated. 
This is commonly regarded as the type species of Notagogus. 
Form. Sf Log. Upper Jurassic: Naples. 
117. Type specimen ; Torre d’Orlando, near Castellamare. 
Purchased , 1837. 
P. 2065. Liner specimen 0T4 in length, shown of the natural size 
in PL III. fig. 7; Torre d’Orlando. Eger ton Coll. 
P. 6866. Impression of a large fish distorted at the lower margin 
of the abdominal region, apparently the counterpart of 
the type specimen of the so-called N. latior ; Torre 
d’Orlando. Presented by Walter Crouch , Esq., 1893. 
P. 1097. Three imperfect young specimens, the largest about 0*06 
in length, exhibiting the internal skeleton of the trunk; 
Torre d’Orlando. The middle portion of the vertebral 
axis of one specimen is shown of three times the natural 
size in PI. III. fig. 8. The pleurocentra and hypocentra 
are observed to he distinct posteriorly, but soon fused 
together in the abdominal region. Egerton Coll. 
Notagogus denticulatus, Agassiz. 
1844. Notagogus denticulatus, L. Agassiz, Poiss. Foss. vol. ii. pt. i. 
p. 294, pi. 1. figs. 1-5, pt. ii. p. 289. 
1851. Notagogus denticulatus , A. Wagner, Abb. k. bay. Akad. Wiss., 
math.-pkys. Cl. vol. vi. p. 65. 
1863. Propterus denticulatus , A. Wagner, ibid. vol. ix. p. 646. 
1881. Notagogus denticulatus, B. Vetter, Mittheil. k. mineral.-geol. 
Mus. Dresden, pt. iv. p. 43. 
Type. Nearly complete fish ; Palaeontological Museum, Munich. 
A species attaining a length of about 0-1. Proportions of head 
and trunk as in N. pentlandi , except that the trunk in the abdo- 
