108 . III. DIST. CHAR. Prototype. 



84. Stipital ( stipitale} having the form of a 

 stipe, or a stem passing into leaves,, as in the 

 Palms and Ferns. 



1. The different kinds of receptacles are 



1. Denticles (denticuli) small, pointed, and generally tooth-shaped 



receptacles, placed, mostly, on the sides of the stirp, at 

 each joint, in Sertularia. 



Calycles (calyculi) little cup-shaped, external receptacles, 

 found also in Sertularia. 



2. Pores (poriy the receptacles peculiar to the genera Mille- 



pora and Corallina. In Corallina the pores are the external 

 extremities of capillary tubes, constituting the interior part of 

 the stirp. In Millepora, also, the pores open into tubular 

 cells, which are frequently disposed in a longitudinal direction. 



3. Stars (stellar) the lamelloso-stellated receptacles in Ma- 



drepora. When the opening of the star has an elongated form, 

 and is more or less flexuous, it is distinguished by the term 



Anfractus; as in Madrepora labyrinthica, Ell. Z. T. 46. 

 f. 34. Madrepora gyrosa, Ell. Z. T. 51. f. 1. &c., &c. 

 2. The Parts of the receptacle are the 



Aperture or mouth (osculuni) the external opening of the re- 

 ceptacle. 



Lid (operculum) a moveable part covering the aperture in some 

 species. Millepora truncata, T. 23. f. 8. Ellis. 



Margin (margo) the part which defines the aperture or mouth. 

 A distinct margin is formed by the top or edge of the wall 

 (paries). 



Center (centrum) the middle part of the aperture. In Ma- 

 drepora this is generally formed by the apex or summit of 

 the axis. It sometimes takes an oblong form, when the stars 

 are elongated, dividing the aperture down the middle, like a 

 partition ; it is then distinguished as the 



