442 THE AMERICAN NATURALIST. [Vor. XXXIV. 
method of sporulation, or multiple reproduction, which takes place 
within a cyst formed by the animal itself. This cyst is thick-walled, 
spherical, and transparent, and, although without stalk or adhesive 
organ of any sort, it regularly sticks fast to small objects in the 
water, being found singly or in groups on sticks or stones. The 
series of changes were not observed in full, but the nucleus of 
the amoeba is reduced by a series of direct divisions into a large 
number of daughter-nuclei. When this number has reached some 
five or six hundred the body of the amceba divides into as many 
independent daughter-individuals, and these are set free by the grad- 
ual decay and bursting of the cyst wall A flagellate stage does 
not occur in Ameba proteus, but the spores enter directly upon the 
amceboid condition. 
'The causes of the multiple division in the encysted condition were 
not determined. The process is not related to sexual reproduction 
and apparently does not occur at regular intervals. Experiments 
by starvation, excess of food, evaporation of the water, and by trans- 
ferring the animals to water from other localities, z.e., by changed 
conditions of existence to bring the amcebas to encystment and 
sporulation, were uniformly without success. H. B. W. 
Arctic Deep-Sea Fauna. — One of the most important results of 
recent Arctic exploration is the discovery of a true deep-sea fauna. 
An address delivered recently to the German Zoólogical Society by 
Dr. Schaudinn,* on the expedition made in 1898 by Drs. F. Schau- 
dinn and F. Roemer to Spitzbergen, contains a preliminary report on 
this fauna. 
This expedition set out to make collections in the Spitzbergen 
Sea, and successfully tried to reach the deep Arctic basin discovered 
by Nansen. This deep, called by Schaudinn the * Nansen Rinne,” 
was reached north of Spitzbergen in 81° 32', and a number of deep- 
sea dredgings were made. A true deep-sea fauna was discovered 
entirely different from the Arctic fauna of the shallow sea surround- 
ing Spitzbergen (and from the other Arctic faunas hitherto known). 
Its most striking feature is the presence of an abundance of Hexac- 
tinellid sponges, a group never found previously in the Arctic regions, 
all of them belonging to new genera. These sponges are so plenti- 
ful that their remains form a very characteristic deposit on the bot- 
tom, composed of the spicules- of the dead sponges closely connected 
and densely interwoven, so as to form a fine network, the meshes of 
1 Schaudinn, F. Verh. Deutsch. Zool. Gesellsch. (1899), pp. 227 ff. 
