31 
firm and thick ; and its colour, as well as that of the calcareous matter 
with which it is filled, is a light yellow. It is figured by Walch, Tab. 
E ' iv. No. 1 and 2 ; by Klein, Tab. xxv. ; and by Faujas St. Fond, 
Histoire Naturelle de la Montague de St. Pierre, PI. xxix. 
A faithful representation of this fossil is given Plate III. Fig. 4 
and 5. This fossil has been sometimes termed Spatangus Mosce, 
trom the circumstance of the Meuse laving the hills at the foot of St. 
1 eter s mountain, where it is found. 
Spatangus purpureas, Tab. xliii. 3, 4, 5, Tab. xlv. 5, Lesk. 
he recent shell, as figured by Leske, Tab. xliii. 3, 4, 5, Tab. xlv. 
’ Ut P artlcularl y in the latter plate, which represents the back of 
the shell, appears to agree exactly with the fossil which I have repre- 
sented Plate III. Fig. 9 , which I purchased from Mr. Forster’s col- 
lection, and which I believe to be a Maltese fossil. 
This fossil is of a subangular cordated ovate shape. Four larve 
pores, near to each other, form, as it were, the centre in the vertex 
w icus rather flat; and at which four ambulacra, and a deep and 
wide dorsal groove, concentre. Each of the four ambulacra is of a 
anceolate petalloidal figure, formed by two bending bands of a double 
row of oblong pores, each pair of which is connected by an oblique 
urrow. The small spaces, or are®, contained within the ambulacra 
appear to have been beset with very minute pores and tubercula • 
and a serrated line, passing through their centre, connects two rows 
dfi ass, J lae - The remaining part of the superior surface is 
i e m o ve arge arese. In the anterior part is the dorsal groove 
. Wlde ’ r ° Unded ’ T d d6ep ’ paS8in S the base to the vertex, form- 
ing a semicircular notch in the margin, and narrowing as it ri ses. 
Un each side of the dorsal groove is a raised triangular flat surface 
bordered by two tuberous ridges, which, rising from the vertex’ 
proceed downwards ; the tubera enlarging, to the margin, and slight 
transverse risings connecting the opposite tubercles. Similar raised 
surfaces descend through each of the other are* ; and similar trans- 
