8 
Portions of some of the ribs (r.) are preserved in the abdominal region, 
showing that they were long, slender, and round in transverse section. 
Remains of some of the hour-glass-shaped neural sjnnes («<?.) are also seen 
in the same region.’ These are very long and slender, and about equal in 
length to the complete neural arches in the anterior part of the caudal region, 
where they are similarly slender and constricted. 
Appendicular Skeleton . — Of the fins, only part of the dorsal ( d .) is 
preserved. It appears to arise at about the middle of the abdominal region, 
and is borne by the ordinary two series of hour-glass-shaped supports. The 
axonosts [a.), which slightly increase in length backwards, are not quite twice 
as long as the baseosts (b.), which are enveloped in the numerous dermal rays 
or actinotricliia. These dermal rays lengthen rapidly backwards, and each 
is a stout rod at its base but becomes subdivided and apparently crossed by 
sparse articulations at the distal end. 
Squamation. — A few r fragments of the large scales, showing their 
characteristic reticulating sutures, are preserved in the abdominal region of 
the type specimen. There are also some isolated scales, which are nearly 
complete though crushed, and one of them is shown in PL II, Pig. 2. These 
scales are very thin and more or less broken up during fossilisation into 
the small areas which are marked out by the reticulating sutures. They also 
exhibit the usual radiating, fine structural lines, besides indications of the 
concentric lines of growth. In shape they closely resemble the scales of 
Ceratodus, being deeply overlapping, with the anterior covered border almost 
truncated, the posterior free edge more sharply curved. 
Subclass— Teleostomi. 
Order — ACTIN OPTERY Grll. 
Family — PAL.ffiONISCJD.ffi. 
Genus— PALJEONISCUS, Blainville, 1818. 
(Nouv. Diet. Hist. Nat., xxvii, p. 320.) 
Gen. Char . — Trunk elongated. Mandibular suspensorium very 
oblique ; mandible slender ; teeth small, conical, and of different sizes. Pins 
relatively small, with minute fulcra, and the rays distally bifurcating, more 
