120 Mr. H. M. Bernard on the 



It will, perhaps, be remembered that I found just such a 

 young colony of Asfrceopora, and, further, I concluded that 

 the morphological differences between Turhinaria and Madre- 

 pora could be best explained by postulating such a young 

 colony in each case ; in Madrepora the central polyp grew up 

 with tiers of daughters springing from its side, while in 

 Turhinaria the ring of daughters shot ahead and formed a 

 cup. 



We are then, I think, justified in deducing il/on?i}50?-a from 

 a parent polyp opening in a mass of spongy coenenchyma, 

 i. €. with a very thick porous wall, contained in a saucer-like 

 epitheca. In MontiiJoray unlike the Madreporidse just men- 

 tioned, the parent polyp formed no projecting cone, but 

 opened level with the upper flattened surface of its thick wall. 

 Similarly the young polyps, opening laterally, do not form 

 protuberant cones ; they appear as mere openings in the 

 coenenchyma, often in contact with the epitheca, in which 

 case the latter may form part of their outer walls. 



The coenenchyma in the young specimen actually examined 

 consists, as seen from the surface^ of jagged flakes, which may 

 be twisted in all directions, but which tend to lie horizontally; 

 the apertures of the polyp-cavities are bounded by the edges 

 of two or more such flakes : in this particular instance the 

 coenenchyma has been secondarily specialized. From the 

 edges of the flakes points project into the polyp-cavity and 

 form vertical series of spines. These series of spines are, in 

 many types, the only remains of the septal apparatus. 

 Examination of all the types, however, shows that the septa 

 were originally lamellate, as in the other Madreporidaj. The 

 large directives are often continuously laminate, and here and 

 there some of the other primaries also ; while, again, what 

 appear to be traces of laminate costte can be found in the 

 coenenchyma of very many types. To these important points, 

 as also to the cause of the widespread degeneration of the 

 septal apparatus, we shall return. 



Starting, then, from such a young colony, with its 

 parent polyp surrounded by a ring of daughters all immersed 

 in a mass of spongy reticulum contained in an epithecal 

 saucer, the stock may develop along different lines. But 

 while in the other Madreporidse the calicles lead and the 

 coenenchyma Jills uj) the interstices^ in Montipora the coenen- 

 chyma takes the lead in the formation of the corallum. I am 

 a^are tliat these expressions may, at first sight, appear very 

 loose ; they are. however, sufficiently useful to render their 

 employiiient justifiable, provided we are quite clear as to 

 Avhat they really mean. We must clearly recognize that the 



