CORALLIFERI. 399 
FAMILY II. 
CELLULARII(1). 
Where each Polypus is adherent in a corneous or calca- 
reous cell with thin parietes and only communicates with 
the others by an extremely tenuous external tunic or by the 
minute pores which traverse the parietes of the cells. These 
Polypi bear a general resemblance to the Hydre. 
CELLULARIA, Lin. 
Where these cells are so arranged as to form branching stems in the 
manner of the Sertulariz, but without a tube of communication in 
the axis. Their substance also is more calcareous. 
Lamouroux separates from them 
CRISIA, 
Where the cells, placed in two (usually alternate) ranges, open on 
the same face(2). 
ACAMARCHIS, 
Where, with the same arrangement we find a vesicle at each open- 
ing(3). 
(1) The Potypzs a Czxtunes of the original. Am. Ed. 
(2) Sertularia eburnea, Gm., Ell., Coral., XXI, a, A;—S. scruposa, Id., XX,c, C; 
—S. reptans, tb., b, B, E, F;—S. fastigiata, Ib., XVI, a, A. 
(3) Sertularia neritina, Gm., Ell., Corall. XIX, a, A, B, C. 
