47 
NAUTILUS simplex* 
TAB. CXXIL 
Spec, Char. Depressed* sphaeroidal* umbilicate* 
plain ; mouth lunate* with the angles truncate* 
embracing the preceding whorl ; siphuncle 
nearest to the inner edge of the septum. 
Thickness about four -fifths of the greatest diameter* 
septa numerous, rather flatter than in Nautilus imperial! s, 
tab. 1. and narrow in the middle. 
This is found rather abundantly in the vicinity of 
Boreham, one mile E. S. E, of Warminster, but often so 
loosely aggregated in parts as to fall to pieces as a mere 
marley green sand, as it is commonly called ; at the same 
time some parts are become more or less solid, and com- 
pact flinty hornstone, or partially filled with carbonate of 
lime in crystals. Under these circumstances it is seldom 
that a good specimen is found, and they vary in shape 
and size, being compressed or rounded, and from an inch 
or two to a foot or more in length. The present spe- 
cimen, from Miss Benett, shewing the place of the 
siphuncle, helps to distinguish it from species which 
might otherwise be confounded with it. It bears a great 
resemblance to Nautilus imperialis, (tab. 1.) but is, how- 
ever, generally rounder in the curyature, and narrower. 
In one massy specimen I found what is deemed an 
Alcyonite imbedded ; it is a sort of organic remains, that 
has repeatedly forked branches, and bearing many clubbed* 
pearshaped* nearly cuplike or folded, apparent tormina- 
