2 BULLETIN 104, UNITED STATES NATIONAL MUSEUM. 



arenaceous foramiuifera are characteristic of cooler and deeper waters 

 and they are much more abundant on the American side at corres- 

 ponding latitudes than on the Euroj)ean side as a result of the differ- 

 ence in oceanic temperature conditions due to the opposite influence 

 of the warm Gulf Stream on Europe and the cold Greenland cm-rent 

 on the American side. As with mollusca. echinoderms, and other 

 groups, several areas of distribution seem to l)e distinguishable on 

 our own eastern coast. The region north of Cape Cod and Georges 

 Banks is very different from the region to the south of this area. 

 Another very definite line of demarcation seems to ])e the region of 

 Cape Hatteras. Many of the northern species seem not to go south 

 of this hne, and their distribution is apparently largely determined 

 in this region by temi)erature conditions. The limits of distribution 

 of the species of warmer waters will be more graphically shown l)y 

 other groups of species rather than those of this family. 



A series of maps has been kindly furnished by the United States 

 National Museum, and these have been used to plot the recorded 

 distribution of each species. By this means definite distributional 

 areas are more or less distinctly made out, although data from many 

 areas is yet unavailable. 



SOURCES OF MATERIAL AM) RECORDS. 



The main source of material for the present work has been the 

 dredgings and hydrograpliic soundings of the United States Bureau 

 of Fisheries steamer Albatross, for this family especialh' the dredgings 

 wliich are much more likely to have an abundance of the coarser 

 material than the hydrograpliic soundings. In addition the work at 

 an earlier time of the Bache, BlueUght, and S'peedweU off the coast of 

 New England has added considerably, especially in the way of rock 

 specimens. The FisJi Hawk has been dredging for many years in the 

 shallower water off our Atlantic coasts and the accumulated material 

 of the United States Coast and Geodetic Survey has also })ecn available 

 butinsmallsamples and usually from very shallow waters. Altogether, 

 however, the amount of material from our Atlantic coast is very 

 considerables Although of little use in this present family the ma- 

 terial dredged by Henderson and Bartsch in the various parts of 

 the West Indies and along the Florida coast will be very useful in 

 supplementing the deeper water material from this region. 



With the work of the Porcupine find KnigJii Errant expeditions and 

 the Nortli Polar and Austro-Hungarian expeditions recorded in the 

 Cliallemjer report, together with the work of Goes and Kiaer on the 

 Ai'ctic and Scandinavian areas, these cover a very large amount of 

 the ocean bottoin. Later expeditious, such as that of the Plankton 

 expedition, supplement the work. Of more intensive work that of 

 the Clare Island survey and of the Ooldseel'pr about the British 



