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gemmation changes the sides of the parent cells to angles, and the 
older corallites, originally in juxtaposition, become separated from one 
another by new series of interstitial calices. 
Affinities of Madrepora.* — Mr. G. Brook points out that this genus, 
with its axial corallites and radial bud-corallites, stands alone ; so far as 
he is aware no other genus approaches it in its mode of colony-formation, 
taking into account the indirect means by which it is attained, and the 
consequent absence of true coenenchyma. It is to be noted, however, 
that the characteristic mode of colony-formation is confined to the 
formation of independent branches, and that at first in all colonies, and 
always so long as incrustation continues, the mode of budding is not 
characteristic. It appears, therefore, reasonable to suppose that the 
species of Madrepora form a specialized group which indicate their 
affinities in the incrusting stage. 
For the present the author adopts the course suggested by Ridley, 
and divides the Madreporidae into two sub-families — the Madreporinae, 
with the genus Madrepora , and the Montiporinae with the genera Ana- 
cropora and Montipora. For a final decision we must wait till we know 
much more than we do now with regard to the structure of the polyps 
and their relation to the skeleton which they produce. 
Edwardsiae .f — Dr. A. Appellof, after remarking that the external 
division of the body into three parts, the absence of a pedal disc, the 
structure, position, and number of the septa are peculiarities of the 
Edwardsiae that have already been sufficiently noticed by preceding 
writers, calls attention to some other points of importance. 
He lays stress on the presence of an ectodermal nervous system on 
the capitulum ; this offers an intermediate stage between the Hexac- 
tiniae on the one hand and the Cerianthidae and some other forms on the 
other. The remaining part of the body of an Edwardsia — with the 
exception of the hinder end — has a thick investment, so that it is not 
adapted for the reception of external influences. It is not clear whether 
or no a nervous system is developed in the physa. On the other hand 
the ectodermal musculature which is developed on all other forms that 
have a nervous system on the body- wall is wanting in the Edwardsiae. 
Some attention is given to the tubercles set in rows on the surface 
which are peculiar to some, and perhaps to most Edwardsiae. Another 
point worth notice is the absence, in the Edwardsiae, of some arrange- 
ments which are frequently found in other Actinians. The pharyngeal 
grooves are either absent or are very feebly developed. Boveri has, on 
embryological grounds, regarded Edwardsia-like animals as the stem- 
forms of all other Actiniae. The want of a slightness of differentiation 
in the oesophageal tube appears to agree well with this conception, as it 
may be supposed that the tube of the stem-form was a simple invagina- 
tion without specially developed parts. 
The absence of septal stomata is, perhaps, common to all Edwardsiae, 
and the point is of importance since, so far as we know, internal septal 
stomata at least are found in all Hexactiniae-Zoanthinae. In this as in 
other points the tribe Protantheae, lately established by Carlgren, shows 
* Journ. Linn. Soc.. xxiv. (1893) pp. 353-60. 
t Bergens Mus. Aarsberet. for 1891, No. 4 (1892) 32 pp. (3 pis.). 
