No. XIII. POLYCYSTINA. 299 



in Messrs. Parker and Jones's table. It will then be seen 

 that thirty-six of the species are common to both areas, and 

 that the remainders contain many nearly related forms, which 

 further opportunity may probably show to have a distri- 

 bution extending more or less northwards or southwards, as 

 the case may be. 



Two new, or rather undescribed, species have been 

 mentioned ; of these detailed descriptions will appear else- 

 where. One of them, Lituola glomerata, is of minute size, 

 not much exceeding T ^ of an inch in diameter, and spiral 

 or nautiloid in mode of growth. It has a thin, arenaceous, 

 non-labyrinthic test, nearly spherical in contour, the longer 

 diameter being often in the direction of the axis, and consists 

 of a few long, narrow, slightly ventricose segments. It can 

 scarcely be said to be new, for it occurs in more than one of 

 the ' Challenger ' dredgings, but it has not hitherto been 

 described or named. 



The other, for which the generic term Hyperammina 

 (vTrspos, a pestle, and a/i/xos 1 , sand) has been adopted, is one 

 of the arenaceous types probably first recognized in the 

 ' Porcupine' dredgings from the North Atlantic in 1869, but 

 since found in many parts of the world. Its form is that of a 

 club, or still more nearly that of a pestle, and it consists of a 

 straight sandy tube with one end rounded and closed, gradu- 

 ally tapering towards the other extremity, which forms the 

 aperture. The Arctic examples are small, none being 

 more than a tenth of an inch in length, but under favourable 

 conditions specimens are met with many times as large. 



The effects of climate, direct or indirect, are noticeable in 

 the modification of form assumed by some of the species, 

 which occur over considerable range of latitude. The Arctic 

 specimens of such species are often dwarfed and usually more 

 compactly built than those obtained in more southern areas. 



NOTE. Whilst working out the Foraininifera of the various samples 

 of material from the sea-bottom, any Polycystina that were found were 

 carefully preserved. They were only noticed in seven of the soundings. 



