Say on Shells, g:c. 387 
cessive partitions to the interior of the spire, as that part be- 
comes too strait for the increasing volume of its body. If the 
above supposition proves correct, the organs of communication 
which pass through the osculi, can hardly be in common, but 
must rather connect the animals by simple contact only, other- 
wise these parts would be broken when the animal changes its 
place by vacating the inferior part of the tube. 
The third variety is then the state of that portion of the 
tube which is inhabited by the body of the animal, and not yet 
interrupted by the septe. 
From the above observations, it is evident that this species, 
and probably the entire genus Favosite under which I have 
placed it, will not arrange properly with the Tubipores, Mille- 
pores, &c. but must be transferred to the Polypiers Lamelliféres 
of Lamarck. And if the Madrepora reiepora of Solander and 
Ellis is a true Porites, as M. Lamarck supposes it to be from 
the appearance of its tubes, I should conclude this genus to be 
very proximately allied to Favosites, by that species and the 
F. Striata having in common the remarkable character of 
fenestrated paries. “But to this character I should conceive a 
generic importance ought to be attached, as indicating a differ- 
ential organization of the artificers. I have no doubt that on 
close inspection of a perfect specimen, the same character 
will be found to exist in F. Gothlandicum, and possibly also in 
F. truncata, if not in the latter only, it may be proper to se- 
parate the genus and to withdraw from Porites the foremen- 
tioned species, retaining to striata as specifically essential, the 
second member of the differential description. 
(To be continued.) 
