CEP HAL ASPID JE. 
195 
45970 a. Two cornua from “ Trochus bed/’ Downton Bridge. 
Lightbody Bequest. 
P. 3247. Cornu from Bone-bed in Upper Ludlow, near Ludlow 
Enniskillen Coll. 
P. 5844. Cornu; Downton Sandstone, Kington. 
Presented by John Edward Lee, Esq., 1885. 
The following specimen is doubtfully assigned to an unknown 
species of Eukeraspis :— 
45989. A long, narrow fragment of smooth fibrous bone, denticu¬ 
lated on the thin long margin, and noticed under the 
name of Plectrodus by Egerton, Quart. Journ. Geol. Soc. 
vol. xiii. (1857), p. 288, pi. x. fig. 2; Downton Sand¬ 
stone, opposite the Paper-Mill, near Ludlow. The den¬ 
ticles are slender, pointed, and longitudinally grooved, and 
are arranged in two series, the inner being largest and 
widely spaced. The bone has more completely the aspect 
of a jaw than the cornua of the typical Eukeraspis. 
Lightbody Bequest. 
A fragment of denticulated bone from a Lower Palaeozoic Boulder, 
found near Danzig, is also described as Plectrodus mirabilis (?) by 
F. Boemer, Palseont. Abhandl. vol. ii. (1885), p. 359, pi. xxxi. 
fig. 26. [University of Breslau.] 
Genus AUCHBBffASPIS, Egerton. 
[Quart. Journ. GeoL Soc. vol. xiii. 1857, p. 286.] 
Syn. Thyestes, E. von Eichwald, Bull. Soc. Imp. Kat. Moscou, 1854, 
pt. i. p. 108 (inaccurate definition). 
Postero-lateral angles of shield more or less produced into acute 
cornua, not exceeding the shield in length. Body depressed, ovoid 
in transverse section; three or four series of dorso-lateral scales 
fused into a continuous plate immediately behind the shield. 
Tuberculations in part very large. 
Having had the privilege of examining some of the original ex¬ 
amples of Thyestes described by Eichwald, Pander, and Schmidt, in 
St. Petersburg, the present writer finds the orbits as distinctly 
marked in the Oesel fossils as in the typical shields of Auchenaspis 
from Herefordshire. Moreover, some of the specimens of Auchen¬ 
aspis egertoni discovered by Mr. Piper in the Ledbury Passage Beds 
exhibit traces of the very large tuberculations and the transverse 
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