90 
found in a fossil state, which much resemble that from 
New Holland ; and much discernment is requisite to di- 
stinguish it from them, and which will be represented at 
tab. 151 . British Mineralogy, being the cast of a species 
which existed probably in aute-diluvian times. Their con- 
struction is always singularly uniform and beautiful : the 
present is perhaps as much so as any : we therefore wonder 
that it has escaped the attention of the curious, for we 
know of no other specimen yet brought to London. 
It is a sort of compressed globe, and, as in others, is 
divided into five principal partitions, each of which has 
four rows of perforations, which we believe fQ be fora- 
mina. These are covered in an elegant manner wi^h minute 
elongated spines, in two rows, with two rows of smaller 
ones at their bases, forming a serpentine line in the centre. 
These smaller ones are somewhat elongated, and in that 
respect differ from the New Holland one. Thus there are 
five grand divisions, which arc also subdivided in the cen- 
tre by a serpentine line, differing from the former in having 
six rows of small acute spines, without any perforations 
under them : on each side of these, in the longitudinal di- 
rection of the shell, are six or seven ovate divisions regu- 
larly set round with flat elongated spines fixed on the cir- 
cumference, and inclining towards the centre, somewhat 
conically, surrounding solid spines, from half an inch to 
three inches or more in length. These spines vary a little 
in proportion of thickness; the lower ones are generally 
thickest, most equal, and bluntest; some diminish towards 
the ends, others thicken a little, those near the mouth are 
sometimes partly spatulate. They are all covered with 
ridges of small tubercles, most prominent towards their 
points, with a spongy appearance surrounding them. The 
mouth is covered with imbricated blunter spines. 
It may be observed that, in describing these, we much 
resemble conchologists, who rather describe the case or 
