in the Madreporide. 287 
cropora, referable, from the character of its budding, to the 
subfamily Montiporinee, fully bears out these views as to the 
nature and importance of the mode of gemmation occurring in 
that subfamily. 
ANACROPORA *, n. gen. 
Madreporide of ramose habit. Axis and apex of branches 
formed by a spongy ccenenchyma. New calicles formed cen- 
tripetally, 7. e. from the base towards the apex; no calicle 
of any kind at the apex. Calicles equally distributed all 
round stem and branches, with a tendency to an arrangement 
in longitudinal series. Septal system well developed, com- 
prising two cycles of six septa each, two (approximately upper 
and lower) primaries being larger than the four lateral pri- 
maries. 
Obs.—Anacropora is based on the new species A. Forbesi, 
described below, and on some forms which occur in the ‘ Chal- 
lenger’ collection of reef-corals, to be hereafter described by 
Mr. J. J. Quelch, of the Natural-History Museum; I have 
had the advantage of Prof. Duncan’s and Mr. Quelch’s opinions 
on this important form, opinions which have been freely and 
kindly given. The general growth and other characters given 
above are essentially the same in all the species. In all the 
growth is low, the branches tending to form inosculations 
between each other; the stem and branches are cylindrical, 
and no distinct tubular calicles are formed. 
From Madrepora this genus differs markedly in the 
centripetal production of the calicles, by which the youngest 
cealicles are always the uppermost. From the subgenus Jso- 
pora, Studer (see above), it differs in the same point, as well 
as in its slender dendroid growth; but the first distinction is 
not so marked at first sight, since the peculiar growth of Jso- 
pora almost necessitates the absence of a distinct apical calicle, 
but (as stated above) the mode of gemmation is centrifugal in 
Isopora, as in Madrepora s. str. Other points distinguishing 
Anacropora from most species of Madrepora are the formation 
of the axis of the branches by a spongy coenenchyma, whereas 
in many (if not all) Madrepore this, in accordance with the 
centrifugal habit of budding, is occupied to a greater or less 
distance from the ends of the branches by the downward pro- 
longations of the septa and the interseptal spaces of the apical 
calicle. The rudimentary condition of the external part of 
the calicle distinguishes <Anacropora; for although it is 
* From ay, privative particle, adkpos, summit, répos, passage or pore ; in 
allusion to the absence of pores from the ends of the branches. 
