.MAUVLAM) (li;(tL()GICAL Sl'KN KV ^^53 



while llatteiit'd Tonus rcscmljlc TruncafitlliKt iritellerstorfi. The reguUir 

 built convex varieties eoiistitiite TruncaluUna buueana d'Orbigiiy ami 

 the less regular form the Truncatulinn rariahilis of the same autlior. 

 T. variabilis is very well r('|ii'c>ciiicil in llic Miucciie (h^'posits at I'liim 

 Point, and elsewhere in the Atlantic Slope Mioeeiic 



Truncalulina lobcUula is probably the most widely distributed of all 

 the Foraminifera. In present oceans it occurs in every latitude from 

 the Arctic waters to the Antarctic Ice barrier. It is most frequent in 

 shallow waters but is present also at depths of 3000 fathoms. 



Its geological distribution begins with comiiact solid forms as far back 

 as the Carboniferous and it is recorded in subsequent formations down 

 to the present day. 



Occurrence. — Nanjemoy FoRiiATiox. AVoodstock. Aquia Forma- 

 Tiox. Upper ]\Iarlboro. 



Collections. — Johns Hopkins University, Maryland Geological Survey. 



Teuxcatulixa uxgeeiaxa (d'Orbigny). 

 Plate LXIT, Fig. 4. 



liotaluta ungerlana d'Orbigny, 1840, Foram. Fosslles Vieune, p. loT, pi. viii. tia^s. 



16-18. 

 Truncatulhia nngeriana Brady, 1884, Clial. Rept., vol. ix, p. 664, pi. xciv, fig. '■>, o-d. 



Description. — Test large, rotaliform, circular, coarsely porous, both 

 sides moderately convex, unequal, depressed slightly on the inferior side 

 at the umbilicus; consisting of three convolutions. The last volution 

 composed of ten to twelve chambers. Septa arched: aperture a median 

 slit of semilunar shape. Diameter, 0.T8 mm. 



This species is common in the Eancocas formation of the ^ew Jersey 

 Cretaceous and it is fairly abundant in the Lower Eocene of Upper Marl- 

 boro, near Seat Pleasant and elsewhere. 



In the Xortli Atlantic Trunentulina ungeriaiia is fairly abundant at 

 from 90 to 600 fathoms, and while it has been found in the South Pa- 

 cific at depths from 27 to 2600 fathoms it is nevertheless a shallow-water 

 form. Specimens occur in the Lower Eocene of Pegwell Bay. England 

 (Burrows) and in the Loudon Clay, and it is recorded in the later Ter- 

 tiaries of southern Europe. 



