No.401.] REVIEWS OF RECENT LITERATURE. 443 
which are filled with mud ; after washing out the mud, about one- 
third of the volume remains as a glittering mass (** Glaswolle "). 
A detailed report on the peculiarities of this deep-sea fauna will 
be given in a separate work entitled Fauna Arctica, and will be, no 
doubt, one of the most interesting additions to our knowledge of the 
Arctic faunas. A. EO. 
Arctic Marine Animals. — The material collected by the Prince- 
ton Expedition to North Greenland in 1899 has been sorted out, and 
part of it has been identified. It proves to be the largest collection 
of Arctic marine life ever made in the neighborhood of Inglefield 
Gulf and Smith Sound. Of the animals reported by former expedi- 
tions (Hayes, Nares, Peary Expedition of 1894), nearly every species 
is represented in the collection, while many additional species were 
taken which have not yet been recorded from these parts. 
The chief value of this collection lies on the zoógeographical side, 
adding new localities to the known range of Arctic forms from parts 
hitherto almost unknown. These localities, situated so far north 
(76—79^), will be very valuable in the construction of a connection 
between many species now known from the Atlantic and Pacific 
parts of the Arctic seas. Some species seem to be truly circumpolar 
in distribution, while in others the connection seems to be inter- 
rupted. For the establishment of such cases an investigation of the 
fauna of this region as well as that of the northern coast of Siberia 
is necessary, and the collections of the Princeton Expedition to 
North Greenland, when published, will, in this respect, add consider- 
ably to our knowledge. A. E. O. 
Notes. — Dr. Thiele reports in Fauna Arctica a new solenogaster, 
Proneomenia thulensis, found by the German Arctic Expedition of 
1898. It is characterized by a radula with many small teeth and 
by a multifid receptaculum. 
In the Munich Sitzungsberichte Mr. A. M. Przesmycki reports his 
success in staining the nucleus of living Opalina and Nyctotherus 
with neutral red. The chromatin elements show the deeper color, 
and the phases of nuclear division may be watched in the living 
organism, 
Text-books of zoólogy have made the statement that the mouth in 
the Infusoria is formed by the simple division of the parental organ. 
In the Heidelberg Verhandlungen Dr. A. Schuberg describes the 
origin of the peristomal region of Euplotes patella as a series of 
