MAUVi.vNi) (ii:()i,<)(;ic Ai. siitvicY 343 



r.iaily iicords its iu'eseiux' in Arctic waters and as Tar simth as Terra 

 (Id l''iir<;(i ,iiiil at the same time it occurs at all jjossildc depths down to 

 •.'•ioo rallidiiis. So ill I he fossil world it is e<[nally widely distrihuted. 

 .Idiu's and I'arkcr iTcoi-d it in llie rpiicr Trias of Derbyshire; Brady and 



r.lakc lia\c idi'iililicd il in cscry di\i>i()ii ol' ihf Lias ol" l*]n;:land. It is 

 rrcHiueiil ly rc|)nrliM| in ilic ( 'rct.iccdiis of l"ji;;land (Sherhorn. Chapman, 

 W'niiht, S<i\\('il>\ . (ic). It is alnindaiit in every division of the Tertiary 

 ami has liccn frc(|iicnt l_v recorded. 



Omirrviicc. — A(^ii\ I''()|;m viiox. Cpp''!- Marllinro. I in ilc southeast 

 of Mason Spriiiii's. 



( 'allrcl mil. — Maryland (icnlouical Survey. 



Cristellaria RAUiATA ( Bomeniann). 

 Plate LXIII, Fig. G. 



Hobulina nuliata Bornemanu, 1855, Zeitsclir. d. deutsch. geol. Oesell., vol. vii, 



p. iJo'l, pi. XV, tig. 1. 

 Cristellaria radiata Bagg, 1896, Bull. 141, U. S. Geol. Survey, p. ".U. 

 Crixiellaria radiata Bagg, 1898, Bull. Amer. Pal., No. 10, p. 29, pi. i, tig. 3. 



Description. — Tost nearly circular, moderately compressed, with cir- 

 cular raised umbilicus; llnal convolution showing ten strongly curved, 

 even chambers, marked externally by raised white septal lines which 

 become less distinct toward the peripheral margin; keel quite definite 

 and of the same snow-white character and color as the raised septa, while 

 the chambers are darker in color and are strongly contrasted from the 

 rest of the shell. ■ The surface is smooth and glistening; the aperture 

 radiate; diameter, 1.26 mm. 



Bornemann's specimens of Cristellaria radiata were from the Oligo- 

 cene (Septarienthon) of Germany. This form resembles Cristellaria 

 rotulaia but has the umbilicus raised, and the septa are also raised as 

 they are not in C ristellaria rotulata. The keel is definite but not pro- 

 duced into a flange as in Cristellaria cuUrata which form it closely re- 

 sembles. 



Occurrence. — ]N"axjemot Formatiox. AVoodstock. 



Collection. — Johns Hopkins University. 



