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TRANSACTIONS OF SECTION D. 863 
preceding year; and it may be seen that here and there a young zocecium or 
branch, noticeable from its pure white colour, is being budded out from an appa- 
rently dead stump. 
This regenerative process may take place in various ways. For instance, an 
old zocecium may form a fresh aperture, and again hecome tenanted by a polypide ; 
or it may grow out into a rootlet or into a growing-point, which will, in course of 
time, give rise to a complex branch. If a rootlet is formed, it may acquire a con- 
siderable length, and then either give rise to a fresh stem as a lateral branch, or it 
may after a time take on the characters of a growing-point, so that the new stem 
is the direct prolongation of what was at first an ordinary rootlet. It is well 
known that the rootlets formed during the normal life of the colony have also this 
power of giving rise to fresh stems. 
More commonly the new branches formed from the stumps of old colonies are 
developed from the old joints; sometimes from the lateral joints, at the points 
where old branches have been thrown off; and sometimes from the axial joints, at 
the points where old axial internodes have been lost. Or if the fracture of a 
branch has taken place across an internode, the broken surface of the internode 
has the power of developing a fresh growing-point, which ultimately gives rise to 
a new branch. 
In certain species of Crista the aperture of the zocecium has the form of a long 
tube. In the lower parts of the colony it is generally found that these tubular 
portions have been lost, and that the part of the zocecium which is left behind is 
protected from further injury by the development of a calcareous diaphragm, which 
prevents foreign bodies from falling into the cavity of the zocecium. Diaphragms 
of this nature have been described in a considerable number of Cyclostomata. If a 
Crisia colony be stained and made transparent, it is found that a zocecium which 
possesses a diaphragm contains a brown body, but no functional polypide. Here 
and there it will be noticed that a polypide-bud is being developed below the 
diaphragm. With the further development of this bud, the diaphragm is absorbed, 
the mouth of the zocecium again growing out into a long tube, which terminates in 
the aperture from which the tentacles of the now functional polypide can be pro- 
truded. 
7. On the Meaning of the Ampulle in Millepora murrayi (Quelch). 
By 8. J. Hickson, M_A., D.Sc. 
In a letter published in ‘Nature’ in 1884, Quelch called the attention of 
naturalists to the presence of certain ampullz in a new species of Mvllepora, which 
he called Millepora murrayt. At the time this letter was written the gonads of 
Millepora were quite unknown, and Quelch naturally supposed that his discovery 
indicated that the sexual products of Millepora were similar in origin and growth 
to those of the Stylasteride, where the male and female products are contained in 
the large and well-known ampulle that have been observed by many naturalists. 
Upon examining the structure of Millepora plicata, the author found that 
the ova are extremely minute, and the sperm sacs borne by the dactylozooids, an 
arrangement quite distinct from that of any known Stylastertd. No signs of any- 
thing corresponding to ampulle were to be seen. 
He was very much puzzled, then, to account for the so-called ampullew of M. 
murray?. 
Early this year Professor Haddon placed in his hands some specimens of a 
Millepora collected by him in Torres Straits. As the specimens are fragmentary, 
it is difficult to say whether they are quite identical with the species described by 
Quelch from Samboangan. At any rate, they possess some of the most marked 
characteristics of Queich’s species, and—a fact of prime importance in connection 
with the subject in hand—they are provided with ampulle. 
These ampullz do not contain ova or embryos in any stage, but modified dacty- 
lozooids bearing very large sperm sacs only 
The eges of Millepora murray? are quite minute, as in Millepora plicata. They 
' are found in the same positions, and they pass through similar, if not identical, 
stages in their maturation and development. 
