288 Mr. 8. O. Ridley on Growth and Budding 
commonly found (I refer to the sunk calicles occurring in so 
many species between the prolonged tubular or nariform ones) 
in some, it is never, so far as my knowledge extends, found 
in all the calicles in any Madrepora. 
Although in its general appearance it differs remarkably 
from even the branched species of Montipora, yet the struc- 
tural differences which separate Anacropora from this genus 
are very far less distinctive than those which separate it from 
Madrepora. In the first place, in spite of its external resem- 
blance to Madrepora, it has the same system of calicular bud- 
ding (viz. centripetal, from the distal coenenchyma) which we 
find well developed in the ramose Montipora; the trabecular 
structure and the two-cycled arrangement of the septa is the 
same in both genera. On the other hand, whereas in Anacro- 
pora there is always an undifferentiated coenenchymal apex, de- 
void of calicles, to the branches, in Montipora this apex appears 
always to bear at least one calicle on its surface. In Anacro- 
pora the calicles are always rather distant and tend to form 
lines, and are slightly raised above the surface, forming low 
hill-like eminences, whereas in the ramose Montipore (e. g. 
digitata, Dana, divaricata and superficialis, Briiggeman), 
which on the whole most closely approach Anacropora, the 
ealicles open flush with the surface, are crowded indiscrimi- 
nately, and no linear arrangement is apparent. In Montipora 
foliosa, it is true, the calicles, especially on the posterior aspect 
of the corallum, are elevated in a similar manner; but the 
foliate growth and the monticular cnter-calicular eminences 
of the upper surface seem to remove this species far from the 
ramose Montipore. It seems to me not improbable that, for 
the reasons I have indicated, these ramose forms may have to 
be separated from the foliate and massive species of Montipora. 
The relations of Anacropora may be thus shortly stated :— 
Anacropora has the general growth of Madrepora, but the 
manner of budding of Montipora. 
The following is a description of the single species referable 
to this genus which I am able to describe; owing to the 
interest attaching to the type, I have allowed myself to give 
its characters at full length :— 
Anacropora Forbest, n. sp. (Pl. XL.) 
Corallum branching frequently, dichotomously, occasionally 
subtrichotomously ; branches given off in succession in a sub- 
spiral manner, the planes of successive bifurcations varying 
from about 30° to 100° with regard to each other; angle be- 
tween branches composing bifurcation 80° to 100°. Stem 
and branches slightly curved, the apical branches more strongly 
