434 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
author looks forward to “the colossal task of redescribing and rear- 
ranging the Madreporaria.” 
Experiments on Ctenophore Eggs.* — Herr A. Fischel corroborates 
the results of Chun, Driesch, and Morgan, and has made further experi- 
ments on the eggs of Beroe ovata. From each of the isolated first two 
blastomeres, a larva with four ciliated ridges arises. From an isolated 
blastomere of the 4-cell stage, a larva with two ridges arises ; and from 
a blastomere of the 8-cell stage, a larva with one ridge ! Each micro- 
mere of the 16-cell stage represents a ridge. 
Porifera. 
Calcareous Sponges of Spitzbergen.t — Herr L. L. Breitfuss has 
studied the collection of the Bremer expedition, and describes 10 species, 
of which Leucosolenia nanseni, Sycetta asconoides, Ebnerella huhenthali , 
JE. schulzei, and Pericharax polejaevi are new. Of the 17 Calcarea 
known to occur off Spitzbergen, 5 are cosmopolitan, 4 occur in the 
Atlantic, 7 are local, and Amphoriscus glacialis is also known from 
Greenland and the Russian Murman coast. No Antarctic occurrence 
of any of these species is known. 
Portuguese Calcarea.J — Herr L. L. Breitfuss describes 11 species 
from the Portuguese coast, which has been but slightly investigated. 
The total number known to occur is 15. The author’s studies revealed 
two new species : — Leuconia coimbrse and L. prava. 
Malayan and Chinese Sponges.§ — Herr Nils Gustaf Lindgren has 
studied a collection of sponges from Java and the Chinese seas, and deals 
in the present memoir with the Monaxonia and Tetractinellida. Of 
these there were 54 species, 21 new. 
Pacific Sponges.|| — Dr. J. Thiele begins by describing a collection 
of Japanese Demospongiae, including many new species and several new 
genera. So far the memoir is of purely systematic interest. 
Position of Sponges. — Prof. Y. Delage^f discusses this difficult ques- 
tion, and inclines to the view that Sponges stand alone in showing a 
reversal of the normal direction of invagination. The endoderm comes 
to the surface to form epidermis, wffiile the ectoderm is intruded to line 
the digestive cavities. If so, the difference between Sponges and other 
Metazoa may well be recorded in a term, and the words Enantioderma 
and Enantiozoa are proposed. 
Prof. E. Perrier** criticises Delage’s proposal to contrast Sponges, 
under the name Enantioderma (ivavn'os, contrary), with other Metazoa. 
Perrier does not object to Sponges being regarded as a distinct series, 
having himself maintained this since 1881 ; he contends, however, that 
a new name is superfluous, that it is difficult to admit that one zoological 
group can be opposed to another, and that the so-called reversal of the 
* Arch. Entwickinech., vi. (1897) pp. 109-30 (1 pi.). See Zool. Central!)]., v. 
(1898) pp. 262-3. f Zool. Jahrb., xi. (1898) pp. 103-20 (2 pis.). 
X Tom. cit., pp. 89-102 (1 pi.). § Tom. cit., pp. 283-378 (4 pis.). 
|| Bibliotheca Zool. (Leuckart and Chun), Heft 24 (1898) pp. 1-72 (8 pis. and 
1 fig.). Comptes Rendus, cxxvi. (1S98) pp. 545-8. 
** Tom. cit., pp. 579-83; Ann. Nat. Hist., i. (1898) pp. 408-12. 
