. III. DIST. CHAR. Prototype. 107 



83. Petiolar (petiolare] having the form of a 

 petiole, or a partial stem connecting the leaf 

 with the main stem or its branches. 



proper cellular fulciments, and in those which are aggregate, 

 when the apertures are terminal, the paries is external, and 

 constitutes the surface of the stirp; as in Madrepora Pa- 

 tella, Ell. Z. T. 28. f. 14. Madrepora flexuosa, Ell. Z. 

 T. 31. f. 5. Tubipora musica, Ell. Z. T. 27. &c. In 

 cumulate fulciments, and in those which are arbuscular with 

 lateral cells, the parietes are mostly internal, and perfectly 

 distinct from the parts which form the surface ; as in Ma- 

 drtpora Ananas, Ell. Z. T. 47. f. 6. Madrepora radiata t 

 Ell. Z. T. 47. f. 8.&c. &c. 



b.) Lamellas (lamella:) are thin, plate-like parts with which the ca- 

 vities in Madrepora are divided. The principal of these 

 are perpendicular, radiating from the axis of the cell to its 

 circumference. The base of a perpendicular lamella is the 

 part which lies next the axis its margin is the edge or ex- 

 tremity, visible at the aperture of the cell. 

 Axis (axis) the middle part of the cell, extending from the ap- 

 erture, or external opening, to the bottom ; and round which 

 the perpendicular lamellas in Madreporte are placed. 



c.) Bottom (fundus) the extremity of the cell, opposite to the 

 external opening. 



d.) Receptacle (receptaculum) the upper extremity of the cell, 

 into the concavity of which the body of the zoophyte is receiv- 

 ed or withdrawn. In 



Sertularia, and in some species of Madrepora, the re- 

 ceptacle is distinct in form and structure from the more in- 

 ternal parts of the cell; in Millepora, Tubiporte, &c. it differs 

 little from the bottom (fundus) or the intermediate part, in 

 which the stipe (stipes. \. former note, p. 96) of the animal 

 is generally fixed. 



