REPORT ON CORALS— EXPLANATION OF PLATES. 211 



S. Style of the gastrozooid. 



A. Circlet of small rough projections of the ccenosteum, which stand out 



from the wall of the gastropore just above the top of the style. 

 DZ, D Z. Dactylopores of the cyclo-system. 

 P. Walls of the ccenosteum separating the adjacent dactylopores from one 



another, the pseudcsepta of the cyclo-system. 

 S'. Style of a dactylozooid. This is seen adhering to the outer wall 

 of one of the dactylopores, which is laid completely open in order 

 to show it in situ. 

 Fig. 4. Portion of the ccenosteum of Spinipora echinata enlarged to show its outward 

 form. The ccenosteum is covered with long grooved spines, which carry 

 the larger dactylozooids. On the sides of these spines, and about their 

 bases, are numerous simple or slightly lipped smaller pores, occupied by a 

 smaller form of dactylozooid. Deeper in between the bases of the spines 

 lie the pores of the gastrozooids, provided each with a style. 



D Z, D Z. Pores of the larger dactylozooids, appearing as grooves in 



the long projecting spines. 

 D Z', D Z'. Pores of the smaller dactylozooids. 

 G Z, G Z. Pores of the gastrozooids. 

 Fig. 5. Portion of the ccenosteum of Labiopora antarctica much enlarged. From a 

 drawing by Mr Charles Stewart, F.L.S. 



G Z, G Z. Pores of gastrozooids with their styles just visible in their depths. 

 D Z, D Z. Pores of larger dactylozooids. 

 D Z', D Z'. Pores of dactylozooids of the smaller kind. 

 Fig. G. View of one of the inner surfaces of a fragment of the ccenosteum of Distichopora 

 coccinca, which has been split in half through the line formed by the 

 pores of the gastrozooids ; showing the arrangement of these pores, and 

 their very long styles. 



G Z, G Z. Pores of gastrozooids. 



G Z'. Young similar pore which has as yet little depth. 

 S, S, S. Styles ; that on the extreme left remarkably long. 

 Fig. 7. Somewhat diagrammatic view of a zooid system of Cryptohelia pudica, divided 

 vertically in half by a section passing through the axis and in the 

 direction of the length of the branch on which the system is situate. 

 The dotted areas indicate cut surfaces of calcareous substance, the 

 structure of which is not filled in in the drawing. The gastropore 

 consists of two portions, an upper and a lower, separated from one another 

 by a circular constricted aperture. The wall of the upper portion ends 

 below in a thin incurved border bounding the circular aperture, and from 



