142 DESCRIPTION OF CORALS. 
mentioned, with those of Sid. galavea. The lamellated tubes extended conti- 
nuously throughout the vertical section 2 inches in height. They exhibited no 
signs of interrupted and renewed growths, nor were they partitioned by trans- 
verse diaphragms, which would have limited partially or wholly the downward 
range of the polype: on the contrary, the animal during life possibly occupied 
the tube to some depth, and enjoyed, by means of the perforated lamellz, cen- 
tral and boundary structures, access to every part of its construction, as well as 
a perfect community of existence with the other polypes dwelling in the same 
specimen. 
Note to Siderastrea Websteri. 
In the collection of tertiary corals for which I am indebted to M. Michelin, 
and received since the notice on Siderastrea Websteri was written, are two 
beautifully preserved specimens of ‘‘ Astrea Ameliana”’ of M. De France, less in 
size, but agreeing in shape with the one represented in pl. 44. fig. 3 of the 
‘Iconographie Zoophytologique.’ In all the characters which may be considered 
generic, there are no differences between the two corals, and the specific di- 
stinctions, if such they may be deemed, consist in the lamellz being more delicate 
and closer together, also in their extremely hispid nature and the great number 
of foramina, whereby the interior of the coral presents a structure very analo- 
gous to that of ordinary Porites. It is considered advisable however to retain 
the specific name of Websteri for the Bracklesham coral, until it shall be fully 
ascertained that specimens of equal development—young, mature and aged— 
of each fossil agree in all essential characters. 
Mr. Dixon has also obligingly lent the describer a larger specimen of Side- 
rastrea Websteri than he had previously seen: it measured more than 4 inches 
in length, about 3 in its greatest breadth, and nearly 14 in thickness. The stars 
exhibited mature but not aged characters, and no variations were noticed from 
the structures mentioned in the text. 
Family Mapreporina. 
Stylophora monticularia, Schweigger. (‘Tab. I. fig. 6.) 
Incrusting, polymorphous ; stars polygonal, very unequal in size and outline, 
surmounted by conical, lamellated mounds; lamellee within the stars 12, sides 
tuberculated, united in the lower part to the axis, disconnected in the upper ; 
