elong’atcd tuherdos or ruo-jic (some enlarged in Fig. 2e), Some indellnite 
impressions in the type sj)eeimen denote tlie presence of large, ■\videly-spaeed, 
conical teeth, and there are indications of a series of minute, closely-arranged 
denticles in the mandible of iSTo. c. Obscure remains, apparently of calcified 
lilamentous appendages of the gill-arches occur behind the head in the latter 
specimen ; and the opercular apparatus, though not clearly shoAvn in either 
fossil, must have lieen narrow. Seven or eight hranehiostegal rays, which 
are broad, expanding distally, and externally tuberculated, are observed 
beneath the mandible on one side of the type specimen (PI. I, Pig. hr), 
while there occurs an niidetermined plate (.r), possibly infraclavicular, below 
the hinder three. 
Axial Skeleton of Trunk . — As is well shown liy the first two specimens 
(PL I, Pig 1; PI. II, Pig. 4), the notochord must have been persistent, and 
there are no undoubted traces of ossiiications in the notochordal sheath. In 
the abdominal region there are not less than thirty-fu'C neural arches, each 
opposed to a pair of small haemal elements, which arc probably homologous 
with those of a Sturgeon, formed externally to tlie notochordal sheath ; in 
the caudal region the number of arches cannot l)c satisfactorily counted, 
ddie ])cdicles of the neural arches in the abdominal region are both robust and 
elongated, and appear to have remained sejiarate at their upper extremity ; the 
corres])ondiug neural spines arc apparently a little calcified, longer and more 
slender than the pedicles, and not fused with these but merely apjiosed by the 
two short limbs of their forked base. In the caudal region the hmmal resemble 
the neural arches and are about ecjual in size, except quite anteriorly where 
they somewhat exceed the latter in development. At the commencement of 
the (;audal region the neural arches become abriqitly smaller than those of the 
abdominal region, and the spines are fused with the pedicles ; the whole arch 
is, indeed, scarcely larger than the pedicles alone of the last abdominal arch. 
More posteriorly, however, the size somewhat increases owing to the length of 
the slender neural spines, which subsequently decrease to the caudal pedicle, 
and gradually become more inclined to the vertebral axis. The inferior 
caudal lobe is supported as usual by especially thickened hannal arches (PI. II, 
Pig. 4 ), and the fulcral scales at the base of the iq)per caudal lobe rest upon a 
laygular, close series of shaider rods, which may be cither neural spines or fin- 
supports distinct from tlie very rudimentary neural arches beneath them. 
Appendicular Skeleton . — The pectoral tins are too imperfectly pre- 
served for description, and were evidently feeble^ ; but the rays are well 
* .Vll the rays sliown in the original of I’l. V. Fig. 1, seem to have been distantly articulated. 
