90 BULLETIN 104, UNITED STATES NATIONAL MUSEUM. 



Ammolagena davata Eimer and Fickert, Zeitsclir. Wiss. Zool., vol. 65, 1899, 

 p. 673.— CusHMAN, Bull. 71, U. S. Nat. Mus., pt. 1, 1910, p. 68, figs. 86-89 

 (in text).— Rhumbler, Foram. Plankton Exped., Toil 1, 1911, pp. 93, 96, 197, 

 pi. 1, figs. 1, 2; Toil. 2, 1913, p. 371.— Pearcey, Trans. Roy. Soc. Edin- 

 burgh, vol. 49, 1914, p. 1004. 



Webhinella davata Rhumbler, Arch. Prot., vol. 3, 1903, p. 229, fig. 55 (in text). 



Description. — Test firmly attached, proloculum oval or pyriform, 

 the basal portion flattened by the surface to which it is attached, 

 second chamber elongate, tubular, free or attached, of nearly uniform 

 diameter, when free circular in transverse section, wall thin, of fine 

 sand grains with an excess of yello\vish or reddish cement, smooth 

 and polished; open end of the tube serving as the aperture. 



Longer diameter of proloculum, 0.5-1.3 mm. 



Distribution. — This is one of the most widely distributed species 

 of the family. In general, however, it seems most abundant in warm 

 waters, on the western side of the Atlantic being found in greater 

 numbers in the Gulf of Mexico and the Caribbean Sea than along the 

 coast from Florida to Cape Cod. Scattered stations carry the distri- 

 bution up the coast to the banks off Cape Cod, but it has not been 

 found in the material from farther north along this coast. South- 

 ward it occurs off Bahia, Brazil, and at scattered stations to the 

 Falkland Islands. Specimens have occurred off Greenland, Faroe 

 Channel, off Norway, off Ireland, and in the Mediterranean. Scat- 

 tered stations in mid-Atlantic give a distribution of the species from 

 the Azores to latitude 40° S. 



Specimens attach themselves to various objects, in tropical waters 

 especially to broken shell fragments, in shallow northern waters to 

 pebbles and coarse sand grains, in deep water to the various otoliths 

 that abound and to many other genera of Foraminifera. 



Both microscopic and megalospheric specimens occur, the former 

 having a comparatively smaller proloculum but much longer tubular 

 chamber. 



Rhumbler mentions that specimens at least occasionally build 

 a definite floor to the proloculum and I have noted a similar condition. 

 The floor over the attachment is, however, usually much thinner 

 than that of the convex surface of the test but not invariably so. 

 The wall of the proloculum usuaUy has a shghtly larger proportion 

 of sand particles than the tubular second chamber but in either case 

 the cement predominates. Occasionally there is a second tubular 

 chamber as the opposite side from the usual one, and in one case 

 I have noted there are two tubes apparently side by side from the 

 same point of the proloculum. 



