128 Mr. H. M. Bernard on the 
daughters appear from the sides of larger parent (“ apical ’’) 
polyps, was described as centrifugal, while that in Anacro- 
pora, in which an apex of undifferentiated coenenchyma takes 
the lead and the young polyps appear in it as it grows, was 
called centripetal. The distinction was thought to be funda- 
mental. On the other hand, the new genus came very near 
Montipora, differing from it chiefly in the fact that the calicles 
in Montipora are typically immersed, while in Anacropora 
they bulge up the surfaces of the branches into mounds or 
eminences. 
The new genus was accepted at once by Duncan in his 
revision of Milne-Edwards and Haime’s system, and he 
allied it with Monttpora. 
The ‘ Challenger’ expedition brought home two new types, 
which Quelch classed under Ridley’s genus, and in 1892 
Rehberg * added another specimen and type, bringing the 
number up to four. The following notes are based upon the 
study of the specimens and fragments (twenty-two in all) in 
the National Collection. These include all the existing types 
except that of Rehberg (A. spinosa), which is in the Ham- 
burg Museum. The examination has resulted in the 
establishment of two new types, one being represented only 
by fragments, the bulk of the specimens being in the Vienna 
Museum. Full details will appear in the official catalogue, 
which is in the press. 
I was for some time quite uncertain as to the validity of 
the distinction made by Ridley between Anacropora and 
Montipora. Slight mounds or elevations on which the calicles 
opened might and do, indeed, occur in Montipora, wherever 
the corallum is very thin, while, on the other hand, we have 
in Anacropora the streaming axial layer leading the growth, 
and forming, as in Montipora, the tips of branches, and a 
further cortical layer formed just as in Montipora. It seemed 
to me, therefore, that while the fundamental identity in the 
structure of the colonial skeleton showed that Anacropore 
were really Montipores, the presence of protuberant calicles, 
which might be a slight return to primitive conditions, hardly 
justified the establishing of a new genus. Comparison with 
other types and with the undescribed material in the collec- 
tion has, however, revealed other characters which are 
important enough to warrant our retaining the genus, but 
uniting it with J/ontipora under a subfamily Montiporinee. 
While, then, the fundamental identity in the structure of 
the coenenchyma shows that Anacropora has branched off 
* Abh. Nat. Ver. Hamb. xii. p. 46. 
