ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
43 
of pressure serve to fill and empty tlie gills. The compass muscles are 
inspiratory, the Gabel-muscles expiratory. Apart from its discussion of 
the bladder system, the paper includes some interesting physiological 
observations, e.g. on the sensitiveness of sea-urchins to carbonic acid 
gas. 
Elasipoda of the ‘ Travaiileur ’ and ‘ Talisman.’ * * * § — M. E. Perrier 
has a preliminary report on the Elasipoda collected by these two vessels 
in 1882 and 1883. Among the deep-sea forms the Holothurians were 
represented by more than 700 individuals. Of these no less than 354 
belonged to the Elasipoda. Altogether there were 9 genera, 2 of which 
are new, and 14 species, 10 of which are new. The new genera are 
called Periamma and Tutela, both belonging to the tribe Elpidiinae. 
The former has on its dorsal surface a transverse row of four papillae, 
while the latter has three small dorsal papillee in each ray, which are 
often hardly visible. 
Holothurians of the £ Princess Alice.’ t — M. E. Herouard gives an 
account of Holothurians collected by the Prince of Monaco in the 
Atlantic. Only 14 species were collected, of which 3 are new. 
Coelentera. 
Extra-European Hy droids, if — Mr. Elof Jaderholm has a report on 
the extra-European Hydroids contained in the Zoological Museum of 
the University of Upsala. In addition to some new species, he describes 
as new genera Spongocladium and Antennellopsis. The former belongs 
to the family Solanderiidoe ; there are no signs of hydrophores, and the 
polypes arise directly from the intermediate space of the reticulate 
skeleton ; the skeleton itself is flexible. S. Iseve is a new species from 
Japan. Antennellopsis is a form likewise from Japan, whose exact posi- 
tion is somewhat difficult to define, as it has a distinct resemblance to 
the Plumulariidae on the one hand, and the Aglaopheniidm on the other. 
The difficulties of determination are increased by the fact that all speci- 
mens at present observed are sterile. 
Porifera. 
Hatural Classification of Asconidse.§ — Mr. E. A. Minchin has a 
preliminary notice on these calcareous sponges, on the study of which 
he has been engaged for some years past. He begins with a protest 
against a notion which has been prevalent since Haeckel’s writings, and 
due largely to them, that the form of Ascon colony is useless for purposes 
of generic or specific determination. Indeed, Mr. Minchin thinks that 
most writers on these sponges have been acquainted only with preserved 
specimens. It is his experience that almost any species of Ascon can 
be identified at sight when one is acquainted with it, and that the mode 
of growth of the colony is a character of great generic value. It is true, 
he adds, that “ it is almost hopeless to recognise an Ascon by its exterior 
from the figures given by Haeckel, but that is hardly the fault of the 
* Comptes Rendus, cxxiii. (1896) pp. 900-3. 
t Bull. Soc. Zool. France, xxi. (1896) pp. 163-8 (2 figs.). 
t Bih. K. Svenska Yet. Acad. Handlgr., xxi. iv. No. 6 (1896) 20 pp. and 2 pla. 
§ Ann. Mag. Nat. Hist., xviii. (1896) pp. 349-62. 
