4 G. HERBERT FOWLER. 



multilobata), which is, by its very nature, outside of, and in a 

 manner independent of, the polyp cavities. 



Of the more primitive (?) condition, Astroides embryo (8), 

 Khodopsammia (2), Dendrophyllia (5), and Fungia (1) stand 

 as admitted examples among the Perforata; Cladocora (4), 

 and Caryophyllia (6) among the Imperforata, all being forms 

 with free calyces ; while of the secondary condition, Madrepora 

 (4), Heteropsammia multilobata (which I hope to describe 

 iu a future memoir), Turbinaria among the Perforata, and 

 Styiophora (7), Seriatopora and Pocillopora (described below) 

 among the Imperforata, are the recorded instances, all possess- 

 ing well-developed coenenchyme. 



In a minor point only do my observations differ from those 

 of von Koch (7), viz. that he figures no mesogloea between the 

 echinulations and the ectoderm ; in other words, according to 

 his figure the persistent ectoderm of the body wall is at those 

 points continuous with the calicoblast layer (fig. 5). The 

 reason which leads me to believe in the existence of a meso- 

 gloea lamina between calicoblasts and external ectoderm, is 

 that at the points where through shrinkage the echinulations 

 have pierced the external body wall, they have carried with 

 them this mesoglcea, which in sections of decalcified specimens 

 preserves accurately their outline, projecting far beyond the 

 shrunken ectoderm. 



Between this external body wall and the corallum lies the 

 system of approximately longitudinal canals with transverse 

 commissures ; in other words, the space between the body wall 

 and the theca is broken up into canals by the points of contact. 

 These canals communicate, as is usual in Perforata, with the 

 canals which permeate the corallum and run also into the 

 polyp cavities. 



The polyps are built on the normal Actinian type. As 

 the calices are placed only on the inner side and on 

 the lip of the crateriform colony, an easy identification of 

 bilaterality is thus afforded, the dividing plane being a radius 

 directed to the centre of the goblet. Approximately at the 

 ends of this dividing plane are placed the axial and abaxial 



