32 HENRY B. BRADY. 



Gewws— HYPERAMMINA, Brady. 



General characters. — Test free or adherent, elongate, 

 tubular ; primordial end closed and rounded ; opposite 

 extremity open and unconstricted, forming the general aper- 

 ture. Texture arenaceous, interior smooth. 



Hyperammina elongata, Brady. 



Evperammiua elongata, 1878. ' Annals and Mag. Nat. Hist.,' Ser. 5, vol. i, 



p. 433, pi. 20, tig. 2 a, h. 



Characters. — Test free, in the form of a straight, or nearly- 

 straight, unbranched, tapering tube ; the wide end closed and 

 rounded, the narrow end constituting the general aperture. 

 Exterior either loosely sandy or compact and smooth, rarely 

 polished. Length up to \ an inch or more (15 or 16 millim.). 



Amongst the dredged sands brought home by Capt. Feilden 

 from the recent North Polar Expedition were one or two 

 specimens of this somewhat striking type. Compared with 

 examples from less boreal latitudes they are very small and 

 not such as can be regarded as average representatives of the 

 species, and for this reason the drawings which accompany 

 the description of them, though quite accurate, must be 

 accepted with some allowance until a series of more charac- 

 teristic figures can be furnished. The type was by no means 

 unknown previously, inasmuch as fine specimens had been 

 found in dredgings made by the stafi" of the " Porcupine" in 

 the North Atlantic, and in material obtained by the " Chal- 

 lenger" at various stations both in the North and South 

 Atlantic and in the North and South Pacific. 



The texture of the test in Hyperammina elongata is some- 

 what variable. In large specimens it is usually loose and 

 sandy, but the sand-grains being fine and of nearly even size, 

 the exterior is, notwithstanding, tolerably smooth. Small 

 individuals are generally much longer in proportion to their 

 diameter than the larger ones ; they are often darker coloured, 

 and their exterior is usually quite smooth or even polished. 

 The interior in all cases is smooth and often stained brown, 

 either by animal secretion or by the adhex'ent remains of 

 dark coloured sarcode. This colouration is quite distinct 

 from the general yellowish hue of the test, which is 

 determined by the presence of small quantities of per- 

 oxide of iron. As has been before stated, the geographical 

 distribution of Hyperammina elongata is very wide, and this 

 is equally true of its bathymetrical range, but though the 

 species has been met with at depths up to 2600 fathoms, the 



