ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
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which one of the two elements of skeleton has practically dropped. In 
all three the epitheca appears in the early stages alone, whilst the great 
mass of the coral substance is built up entirely by septa and their synap- 
ticular connections. These three genera do not lend themselves to any 
trustworthy phylogenetic arrangement. It is safest to deduce them 
independently from some more primitive coenenchymatous coral, which 
is now perhaps only represented in the earliest encrusting stages of 
Astrseopora and Madrepora. 
Budding in Corals.* — Dr. G. v. Koch describes in Alveopora retusa 
Yerrill the Zwisclunknospung which he previously observed in the fossil 
form Favosites gotJilandica , and also discusses the septal budding of 
Favia cavernosa Forsk. It is difficult, however, to summarise the 
matter profitably without the beautifully clear figures which accompany 
the original. 
Reactions of Metridium to Food and other Substances.f — Mr. G. 
H. Parker has made some observations on the habits of this common 
American sea-anemone. He finds that the outer surfaces of the column 
rnd aboral disc are not ciliated, and are incapable of being stimulated 
by the soluble constituents of the food. The tentacles are covered with 
cilia, but the action of these was not noticeably influenced by the soluble 
constituents of food. The cilia of the siphonoglyphe wave invariably 
inwards, and it is possible that the stimulation of the surfaces of this 
orifice by meat-juice gives rise to a peristaltic movement in the gullet. 
The cilia of the lips usually wave outwards, but the direction of their 
stroke can be temporarily reversed by meat-juice. Application of this 
juice to the lips calls forth peristaltic movements of the gullet. The 
effects of frequently repeated weak chemical stimuli on one side of the 
oral disc are not transmitted in any appreciable degree to the other side. 
In other words, the nervous functions are not centralised. In an ex- 
panded quiescent Metridium the tentacles point away from the mouth, 
and their cilia wave towards the tips. The cilia in the siphonoglyphe 
wave inward, those on the lips outward. If any indifferent substance is 
dropped on these parts it is carried along with the ciliary currents ; if 
a piece of meat be placed on the tentacles, these turn their tips towards 
the mouth and their cilia carry the meat to their free ends, from which 
it drops on the lips ; the cilia of the lips thereupon reverse, and the 
meat passes down the gullet, partly by ciliary action and partly by 
peristaltic movements. 
Hydroids of Ternate.J — Herr B. von Campenhausen describes some 
Hydroids from a collection made by Prof. Kiikenthal at Ternate. Of the 
twenty species, three are new : — Cryptolaria ternatana t Calyptothujaria 
opposita , and Caminothujaria molukkana g. et sp. n. 
Porifera. 
New Hexactinellida.§ — Dr. I. Ijima describes several new sponges 
from Sagami Bay. Three of them are representatives of new genera ; 
* Morphol. Jalirb., xxiv. (1896) pp. 167-77 (8 figs.). 
t Bull. Mus. Comp. Zool., xxix. (1896) pp. 107-19. 
t Zool. Anzeig., xix. (1896) pp. 103-7. § Tom. cit., pp. 249-54. 
