MARYLAND GEOLOGICAL SURVEY 481 



Suborder PORCELLANEA. 

 Family MILIOLID/E. 



Genus MILIOLINA Williamson. 

 "Shell free; convoluted; inequilateral; usually oblong; consisting of 

 numerous segments, each of which in turn extends over the entire length 

 of the shell. Convolutions not disposed in the same plane, but con- 

 stantly changing their direction, so that parts of from three to six visible 

 segments contribute in various proportions to form the external surface 

 of the shell. Septal orifice large, alternately occupying opposite extremi- 

 ties of the shell ; furnished with an appendicular tooth." Williamson. 



MiLiOLiNA SEMiNULUM (Linne). 

 Plate CXXXIII, Fig. 12. 



Serpula seminulum Linne, 1767, Syst. Nat., 12 edit., p. 1264, No. 791 ; IS edit. 



(Gmelin's), 1788, p. 3739, No. 2. 

 Miliolina seminulum Williamson, 1858, Rec. Foram. Gt. Brit., p. 85, pi. vii figs 



183-185. 

 Miliola Marylandica Lea, 1833, Contrib. to Geol., p. 215, pi. 6, fig. 227. 

 Miliolina semimdmn Bagg, 1898, Bull. Amer. Pal., No. 10, p. 33. 



Description.— Test free, calcareous, imperforate; elliptical or oblong 

 in outline; consisting of five visible elongate, smooth segments. The 

 segments are arranged in an inequilateral manner around a Miliolina 

 axis. The two outer ones extend the entire length of the shell with ends 

 overlapping and the aperture in the extremity of the larger segment 

 forms a horseshoe-shaped opening with appendicular tooth in its center. 



This species does not extend back prior to the Eocene. It is in existing 

 oceans one of the most cosmopolitan species, extending from the extreme 

 Arctic regions through the equator to the Antarctic region in the south 

 and it is present at all depths from shallow pools to 3000 fathoms. 



It is more abundant in Virginia than in Maryland. This species of 

 Miliolina was the first foraminifer described from the Maryland Mio- 

 cene. It was figured and described by Isaac Lea under the name Miliola 

 marylandica in his " Contributions to Geology." From his description 

 and figure there can be no doubt about the species referred to as a typical 



example of M. seminulum. 

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