310 Mr. H. J. Carter on 
to Porosphera, and Certopora crispa et favosa, Goldfuss, to 
Thalimina respectively. 
It is worthy of notice that the specimen of Cylindrohy- 
phasma Milaschewitschi, which consists of a cylindrical por- 
tion 2 inches long and 9-24ths inch thick, should have its 
cavity filled with sea-bottom—that is, a heterogeneous mixture 
of sand and minute Foraminifera &c., like that which I have 
stated to occur in Parkeria. How does this material, viz. 
sea-bottom, get there? In a specimen from the “ Chalk 
Marl” just received from Mr. Charles Moore, F.G.S., there 
is the same condition, viz. the growth of a Hydrozoic (? cal- 
careous) polypary or corallum, somewhat like that of Parkeria, 
round a nucleus of “ sea-bottom ’’—that is, quartz-sand and 
minute Foraminifera &c. Certainly it was the habit of these 
Hydrozoa, as it was that of Stromatopora, preceded by their 
soft, sarcodic, proliferous membrane, to run in between and 
over every thing with which they came into contact. I possess 
a block of Stromatopora from the Devonian Limestone in the 
neighbourhood of Ipplepen (near Torbay) and its environs, in 
which this is represented upon a large scale, there being frag- 
- ments of half a dozen other things besides shells &c. in a 
mass of Stromatopora which must have originally been two 
or three feet at least in diameter. It was given to me by my 
friend Mr. William Vicary, of Exeter, who has perhaps as 
fine a collection of Stromatopora as any in existence. 
In his concluding remarks Dr. Steinmann places Stromato- 
pora under Spheractinia; Loftusia under Ellipsactinia; and 
Parkeria with Porosphera. 
Porosphera is adopted, as before stated, for Phillips’s Mille- 
pora, generically ; and unquestionably the use of Millepora 
here is confusing; at the same time it shows how sensible 
Phillips was of the real nature of this fossil originally. 
Dr. Steinmann’s paper is beautifully illustrated, and an 
advance upon the subject which cannot be ignored by those 
who wish to keep pace with paleontological knowledge. The 
slight discrepancy that exists between my figure of Hydrac- 
tinia arborescens and that given by Dr. Steinmann arises from 
the latter having been lithographed from a rough sketch and 
the former from a finished drawing. 
As regards the Stromatoporoid origin of Hozoon, however 
(footnote, p. 114), of which a type specimen is now before me, 
it might be observed that ‘‘moss-agates”’ from the trap of 
Western India frequently present arborescent glauconite as 
much like organic remains as the so-called Hozoon is remote 
from such resemblance. When, therefore, the figure in the 
metamorphic rock is even as like organic remains as that in 
