18 BULLETIN 71, UNITED STATES NATIONAL MUSEUM. 



Ladrone Islands and southward through the Philippines to the region 

 north of Australia. 



Besides these three, which are rather definite in their limits, there 

 are many more minor faunas which may be made out, but which are 

 not of sufficient importance to be mentioned here. One example, for 

 illustration, is the cold area extending around the northern portion 

 of the North Pacific and Bering Sea. This is marked by such species 

 as Polystomella sibirica Goes, etc. 



On the whole, while the North Pacific is not as interesting perhaps 

 as is the North Atlantic, there are portions of it which are very rich 

 in species which are represented by an abundance of specimens. 



The systematic portion of the work has been written on the basis 

 of the distribution in the North Pacific entirely, and the stations are 

 given with this in mind. Occasionally mention of other regions is 

 made, but only when this has some special bearing on this region. 



SYSTEMATIC PART. 



Order FORAMINIFERA. 



Pseudopodia of fine threads, freely anastomosing to form a network; 

 test typically with many minute foramina, in one family with a 

 single aperture ; wall of the test composed of chitinous or calcareous 

 material when secreted, or of agglutinated sand, sponge spicules, 

 shells, etc., usually secreting either no silica or a very little under 

 certain conditions. 



[Family 1. GROMIDiE. 



Test usually chitinous, sometimes with a covering of foreign 

 material; apertures one or more; as a rule inhabiting fresh and 

 brackish waters. 



As all the material available for the present work consists of 

 strictly marine material, usually dredged from altitudes of several 

 fathoms to the greatest depths, members of this family are not to be 

 expected. They undoubtedly occur in the fresh or brackish waters 

 of the coasts and larger islands. They will not be further considered 

 here.] 



Family 2. ASTROEHIZID^. 



Test composed of agglutinated material for the most part, occa- 

 sionally with a chitinous inner layer, consisting of a chamber with 

 several openings or a tubular test open at both ends, or in certain 

 forms, of a closed chamber with a single aperture, but throughout 

 the family the test is not divided into a series of chambers. 



The tests here included in this family are all of agglutinated ma- 

 terial, but in some genera, such as Rhizammina, there is a chitinous 



