CEPHALASPIDJ5. 
189 
the encircling scutes being relatively smaller and more numerous. 
In some Forfarshire specimens, moreover, the superficial ornamen¬ 
tation is in the form of distinct tubercles. 
The new specimens obviously confirm Lankester’s suspicion, that 
there is no “ nuchal ” plate behind the anterior shield, as was con¬ 
sidered possible by Egerton. 
Numerous sections of the trunk in various directions show no 
traces of a hard internal skeleton, and thus are also confirmatorv of 
previous conclusions on the subject, based upon the study of exam¬ 
ples of the typical species. 
The only fin preserved in Mr. Piper’s fossils is the dorsal, which 
seems to be incompletely shown in No. P. 6023. There are no well- 
defined fin-rays, the supporting structures being small, oblong, cal¬ 
cified plates, closely fitted together, and placed end to end in vertical 
parallel series. The arrangement is very suggestive of that of the 
fragmentary fossils described by Lankester from the Bush Pitch Beds 
under the name of Kcdlostrakon podura (see p. 175). 
45944. Type specimen of Cephalaspis ornatci , Egerton; Tilestones, 
Ludlow. Lightbocly Bequest. 
P.673, P.676. Two portions of shields; Auchenaspis-G rits (Pas¬ 
sage Beds), Ledbury, Herefordshire. Egerton Coll. 
P. 3238-39. Four similar specimens, one being in counterpart; 
Auchenaspis- Grits, Ledbury. Enniskillen Coll. 
P. 6023. Block of sandstone with more or less fragmentary remains 
of about twelve individuals, shown, of the natural size, in 
PI. X. fig. 1 ; red sandstone in Passage Beds, Ledbury. 
Presented by George H. Piper, Esq., 1889. 
P. 5317. Crushed portions of the shield and scaly trunk of two 
associated individuals, one displaying the operculum; 
red sandstone, Ledbury. 
Presented by George II. Piper, Esq., 1887. 
P. 6260. Imperfect shield and anterior portion of the caudal region, 
the latter fractured and showing the ventral scales (PI. X. 
fig. 4, v.) ; red sandstone, Ledbury. 
Presented by George II. Piper, Esq., 1890. 
P. 6261. Imperfect shield and anterior portion of the caudal region, 
showing well-preserved dorsal ridge-scales ; red sandstone, 
Ledbury. Presented by George H. Piper, Esq., 1890. 
P. 6108. Portion of the anterior shield broken in such a manner as 
to expose the irregular polygonal dermal calcifications 
