VENTRICULITES. 949 
those on the cavity of the outer case. The specific name, 
inclusa, was suggested by this character ; which, however, is 
_ only accidental, for the specimens imbedded in chalk, are 
_ simply surrounded by the stone. It is the calcareous nature 
_ of the fossil, which renders it so easily separable from the in- 
_ vesting flint, while its cells afford numerous points of attach- 
- ment, and these remain as casts in relief on the interior of 
mu 
the hollow case: I have not observed the same regularity of 
_ structure on the inner as on the outer surface. 
The reticulated integument of this zoophyte resembles in 
structure that of V. radiatus. With regard to the latter, 
I should state that Mr. Toulmin Smith * discovered that the 
-inosculating fibres of the intimate tissue formed an octa- 
_hedral plexus at each knot or point of union ; and this strue- 
ture Mr. Smith regards as peculiar to the Ventriculites, and 
states that he detected it in all the fossils he has arranged 
under the name Ventriculide. No spicula have been de- 
tected in the integuments. 
Until more ample and satisfactory evidence is collected as 
to the nature of these fossils, the interests of science will 
be best promoted by allowing the question to remain sub 
judice, and restricting the term Ventriculites to those zoo- 
phytes which possess the general characters of the type to 
which the name was originally assigned ; namely, a vasiform 
or subcylindrical frame-work, terminating at the base in a 
point, and fixed by radicle processes ; the substance consist- 
ing of a plexiform fibrous tissue ; externally constituting a 
reticulated integument, the meshes disposed in a radiating — 
manner from the base to the periphery ; the inner surface 
studded with open cells regularly arranged. 
In the former edition of this work the Ventriculites were 
placed with the Polypifera from the structure of the open- 
* “On the Ventriculide ;” a series of papers published in the 
Annals of Natural History, with many figures of cretaceous zoophytes, 
By Toulmin Smith, Esq. 
