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SUMMARY OF CURRENT RESEARCHES RELATING TO 
offers a remarkable example of tbe modifications which may be effected 
in the form and mode of fixation of an animal by the different develop- 
ment of one of its parts. When quite young the polyp is cylindrical, 
and its septa form two cycles which may be represented by the formula 
6 — f- 6. As is well known, the adult has an oval calyx. By the con- 
tinuous study of growing forms the author has been able to explain how 
the change is effected. When a polyp is 2 to 3 mm. high, one of its 
tentacles, the corresponding cavity, and the edge of the peristome become 
more developed. The deposit of calcareous particles follows the activity 
of this lateral growth, and the result is that the edge of the calyx is 
jirolonged, by curving towards the surface by which the polyp is fixed. 
When the tissues, thus elongated, come in contact wtth that surface, a 
connection is established between it and them, sclerites are deposited at 
this point, and henceforward, the polyp is doubly fixed, first by its 
primitive base, and, secondly, by the edge of its calyx. On the pro- 
longed and curved part deposits are formed as in the rest of the calyx, 
but they are also curved, while retaining the size proportional to the 
order of cycle to which they belong. The calyx now begins to be oval, 
and the whole of its edge is no longer tangential to a plane perpendicular 
to the axis of the cylinder. As the animal grows and its tentacles 
increase in number, the side which was at first inclined is again gradually 
raised. It is especially at this end of the long axis of the oval that there 
are produced the increase of the elements and of new groups of chambers. 
The oval thus gets longer, and the flabellate form becomes more and 
more marked. It is, moreover, at this end that the new groups of septa 
which are added are sometimes very different in size as compared with 
the lateral groups. 
Prof. Lacaze-Duthiers points out that we have here an instance of 
the utility of following the development of organisms so as to recognize 
and properly interpret the successive changes through which they pass ; 
it is too in this way that Zoology may be called experimental. 
Post-embryonic Development of Fungia.* — Mr. G. C. Bourne has 
been able to study the various phases in the life-history of Fungia , from 
the youngest fixed form with twelve septa up to the fully formed free 
disc-shaped adult, and of these he now gives a detailed account. 
For convenience and clearness he makes use of a definite terminology, 
applying the term trophozooid to the individual Caryophyllia-like form 
which ®is developed directly from the ovum ; this may give rise to one 
or more anthoblasts, by which name the buds may be distinguished from 
the individual which gave rise to them ; two or more anthoblasts united 
to form a colony may be called an antliocormus. The discoid Fungia- 
form, whether free or attached, is an anthocyathus, while the term antho- 
caulus is applied to the pedicle which carries the anthocyathus, and after 
the detachment of the latter remains in connection with the cormus, or, 
in the case of isolated tropliozooids, remains fixed to a foreign body, and 
usually gives rise to a new anthocyathus. 
Attention is called to the fact that the septa in the trophozooid, and 
in the anthoblasts formed from it, arise in the same way and have the 
same relations as in any ordinary solitary coral ; that the anthocyathus 
* Sci. Trans. Roy. Dublin. Soc., v. (1893) pp. 205-38 (4'pls.). 
