107 
appear to have known of this fossil, although he relates, that he had 
received from his father many fossil shells which had been dug up in the 
fields of Miniato, near to the hills of Cerretani.* 
This fossil is of a yellowish white colour, and of a roundish tuber- 
ous shape, it being furnished with several processes of different sizes, 
which terminate in different ways ; some being rounded, and others 
flattened. An opening of somewhat of an oval form, answering to 
the mouth of the shell which it invests, exists on that side which is free 
from the processes just mentioned. By the side of this opening three 
of the branches terminate abruptly, as if broken or worn down, shew- 
ing that they are internally of a laminated structure. Upon examin- 
ing the surface with a magnifying glass, it is found to be granulated by 
innumerable minute risings, bearing somewhat of a mammillated ap- 
pearance. Innumerable minute openings are also seen over the 
greater part of the surface, and many of them in the centre of the 
risings just described. 
This alcyonium is formed on a nerite, which is the case also in the two 
other specimens which I possess ; the nerites, thus incrusted, bear- 
ing every appearance of fossil shells. This kind of shell, the Abb6 
observes, is the most frequent nucleus of this fossil alcyonium, found 
in these hills ; but he has also seen specimens enclosing other univalve 
shells. 
A curiously formed fossil alcyonium is depicted Plate X. Fig. 6 ; 
it is now composed of a very dense limestone, the hardness and weight 
of which, as well as the colour, sufficiently evince that it possesses a 
very considerable portion of iron. From its inferior tapering part, which 
is a portion of its pedicle, it gradually swells, and is then continued, 
in a flattened cylindrical form, about four inches, when it gradually 
contracts and terminates in an irregular surface, perforated witfi seve- 
ral small circular openings. Other openings, much smaller than these. 
* Metallotheca Vaticana, Page 129. 
