STUDIES IN FORAMINIFERA 



217 



Family Polymorphinidae d'Orbigny, 1846 



Genus Pyrulinoides Marie, 1941 



Pyrulinoides thurrelli Tappan, new species 



Plate 68, Figure 13 



Test free, elongate, fusiform in outline, circular in 

 section; chambers added 180 degrees apart, in a biserial 

 arrangement, much overlapping, increasing rapidly in 

 size, final chamber extending back about three-fourths 

 the distance to the base on one side, only about one- 

 third the distance on the opposite side ; sutiu-es strongly 

 oblique, flush; wall calcareous, finely perforate, surface 

 smooth; aperture terminal, radiate. 



Length of holotype 0.94 mm., greatest breadth 0.42 

 mm. Paratypes range from 0.60 to 1.12 mm. in length. 



Remarks: Pyrulinoides thurrelli, new species, differs 

 from P. obesa Marie in the larger size, more regularly 

 fusiform outline, greater chamber overlap, more oblique 

 sutures, and fewer, larger chambers. The species oc- 

 curs in the Grandstand and Topagoruk formations. 

 The specific name is in honor of R. F. Thurrell, geologist, 

 formerly with U. S. Geological Survey. 



Types and occurrence: Holotype (USNM P4553) 

 from a core at 466-476 feet in the Grandstand forma- 

 tion, in Skull Cliff core test 1, lat. 70°55' N., long. 

 157°38' W., between Point Barrow and Point Franklin, 

 northern Alaska. 



Unfigured paratype (USNM P4554) from a core at 

 523-533 feet in the Grandstand formation and unfig- 

 ured paratype (USNM P4555) from well cuttings at 

 3,160-3,170 feet in the Topagoruk formation, both 

 from Simpson test well 1, at lat. 70°57'05" N., long. 

 155°21'45" W., west of Cape Simpson, northern 

 Alaska. 



Family Buliminidae Jones, 1876 



Genus Praebulimina Hofker, 1951 



Praebulimina eeabeensis Tappan, new species 



Plate 69, Figures 14-16 



Test free, elongate, flaring, chambers in a high spiral, 

 triserially arranged, low, somewhat inflated, increasing 

 gradually in size, those of final whorl somewhat higher 

 and subglobular; sutures distinct, depressed, horizontal; 

 waU calcareous, finely perforate, surface smooth; aper- 

 ture loop-shaped, at the inner margin of the final cham- 

 ber, extending up into the chamber face. 



Length of holotj^je 0.26 mm., breadth 0.18 mm. 

 Paratypes range from 0.10 to 0.42 mm. in length. 



Remarks: Praebulimina seabeensis, new species, dif- 

 fers, from P. venusae (Nauss) in the larger size, more 

 bluntly rounded base, less flared test, and lower final 

 whorl of chambers. 



The specific name refers to the Seabee formation, in 

 which this species is found. 



Types and occurrence: Holotype (USNM P4564) 

 and unfigured paratypes (USNM P4565) from a core at 

 591-601 feet, figured paratype (USNM P4566) and un- 

 figured paratype (USNM P4567) from a core at 519- 



529 feet, and figured paratype (USNM P4568) and 

 unfigured paratypes (USNM P4569) from a core at 

 584-591 feet, all in the Seabee formation, in Umiat 

 test well 1, at lat. 69°23'52" N., long. 152°19'45" W., 

 west of Umiat, in the northern foothills of the Brooks 

 Range, northern Alaska. 



Family Discorbidae Cushman, 1927 



Genus Eurycheilostoma Loeblich and Tappan, 1957 



Eurycheilostoma grandstandeneis Tappan, new species 



Plate 68, Figures 19-25 



Test free, trochoid, extremely high spired, all whorls 

 visible dorsally, only the final whorl visible on the con- 

 cave, widely umbilicate ventral side, triserial through- 

 out, chambers increasing gradually in size in the early 

 portion, forming a gradually enlarging spire, later 

 chambers enlarging rapidly and becoming inflated, so 

 that there may be a distinct change in the diameter of 

 the test with the final whorl, the final chamber occupy- 

 ing one-half to two-thirds of the ventral side of the 

 test; sutures distinct, flush in the early spire, depressed 

 in the later portion; waU calcareous, finely but distinctly 

 perforate, surface smooth, aperture an arch at the inner 

 margin of the final chamber on the ventral side opening 

 into the umbilicus, partly covered over by an extensive 

 although narrow flap which has a serrate border in all 

 well preserved specimens, an apertiu-al reentrant occur- 

 ring at both extremities of this flap. 



Greatest diameter of holotype 0.16 mm., height of 

 spire 0.31 mm. Paratypes range from 0.13 to 0.26 mm. 

 in diameter. 



Remarks: This species differs from E. altispira Loe- 

 blich and Tappan in being larger and extremely high 

 spired and in having the conical early portion com- 

 monly followed by an abrupt flaring of the final whorl. 

 It differs from E. robinsonae, new species, in being much 

 higher spired, with a pointed apex and nearly flush 

 sutures in the early development. 



Eurycheilostoma grandstandensis occurs in the Grand- 

 stand and Topagoruk formations. 



Types and occurrence: Holotype (USNM P4595), 

 figured paratypes (USNM P4596 a,b), and unfigured 

 paratype (USNM P4597) from a core at 555-565 feet, 

 unfigured paratypes (USNM P4598) from a core at 

 433-438 feet, unfigured paratypes (USNM P4599) 

 from a core at 543-545 feet, all from the Grandstand 

 formation; unfigured paratypes (USNM P4600) from 

 a core at 1,030-1,040 feet, unfigured paratypes (USNM 

 P4601) from a core at 1,070-1,080 feet, unfigured para- 

 types (USNM P4602) from a core at 1,247-1,267 feet, 

 figured paratype (USNM P4603) and unfigured para- 

 types (USNM P4604) from a core at 1,360-1,370 feet, 

 figured paratype (USNM P4605) and unfigured para- 

 types (USNM P4606) from well cuttings at 1,580- 

 1,590 feet, unfigured paratypes (USNM P4607) from 

 well cuttings at 1,760-1,770 feet, imfigured paratypes 

 (USNM P4608) from well cuttings at 1,870-1,880 feet, 

 unfigured paratypes (USNM P4609) from a core at 



