STUDIES XN FORAMINIFERA 



229 



globular rather than semilunate chambers. The aper- 

 tural characters are similar, each having a broad 

 umbilical flap with apertural reentrants at its two 

 extremities. 



Superficially, high-spired species of this genus may 

 resemble Bulimina d'Orbigny or Praebulimina Hofker, 

 but the present genus has a completely different broad 

 low aperture and open umbilicus, with the flap extend- 

 ing over the umbilicus, whereas the Bulinainidae typi- 

 cally have loop-shaped apertures and an internal 

 toothplate. 



Eurycheilostoma altispira Loeblich and Tappan, new species 

 Plate 73, Figures 3, 4 



Test free, tiny, trochospiral, high spired, umbilical 

 side flattened to concave, deeply umbUicate, periphery 

 rounded, chambers inflated and increasing rapidly in 

 size, all of the two and a half whorls visible on spiral 

 side, only the three chambers of the last whorl visible 

 on umbilical side, with the final chamber occupying 

 over half the periphery and the umbilical side; sutures 

 distinct, umbilical side depressed, spiral side less 

 depressed; wall calcareous, finely perforate, surface 

 smooth; aperture a broad low arch at the inner margin 

 of the final chamber on the ventral side, covered over 

 by a narrow flap extending for a distance about half 

 the diameter of the test, leaving a reentrant at its 

 two extremities. 



Greatest diameter of holotype 0.19 mm., height of 

 spire . 23 mm . Figured paratype 0.18 mm . in diameter, 

 0.17 mm. in height. Unfigm-ed paratypes vary from 

 0.13 to 0.29 mm. in diameter and 0.10 to 0.29 mm. in 

 height. 



Remarks: Eurycheilostoma altispira, new species, 

 differs from Discorbis scanica Brotzen in being higher 

 spired, with less inflated chambers and in having a 

 broader apertural flap. 



Types and occurrence: Holotjrpe (USNM P4882), 

 figured paratype (USNM P4883), unfigured paratypes 

 (USNM P4884 and P4885) from the Goodland forma- 

 tion (Albian), at Lake Worth Dam, 5.5 miles (airline) 

 northwest of the courthouse in Fort Worth, Tarrant 

 County, Texas. Collected by H. T. and A. R. 

 Loeblich, Jr. 



Unfigured paratypes (USNM P4886 and USNM 

 P4887) from the Goodland formation, 3.8 miles west 

 of Montgomery Street on Vickery Boulevard (Old 

 Stove Foundry Road), at Cragin Knobs, Fort Worth, 

 Tarrant County, Texas. Collected by H. T. and 

 A. R. Loeblich, Jr. 



Sestronophora Loeblich and Tappan, new genus 



Type species: Sestronophora amoldi, new species. 

 (Derivation: sestron, Gr., n., sieve + phor, Gr., suffix, 

 to bear or carry; gender feminine.) 



Test free, large, trochospiral, nearly planoconvex, 

 periphery acute and with a keel; all whorls visible on 

 the strongly convex spiral side where chambers are 

 of greater breadth than height, somewhat oblique and 



overlapping at the periphery, only the chambers of 

 the final whorl visible on the nearly flat, umbUicate 

 side, the broad ventral umbilicus covered by a series 

 of plates arising from the umbilical margin of each 

 chamber and pierced by numerous very large openings 

 leading through the plates to the open umbUical area 

 beneath, which also opens laterally beneath the plate 

 into the various chamber cavities; sutures distinct, 

 somewhat thickened, gently cm-ved and inclined back 

 along the periphery and depressed on spiral side, nearly 

 radial and more strongly depressed on umbilical side; 

 wall calcareous, finely perforate, surface smooth; 

 aperture a low slitlike opening on the umbilical side 

 and at the margin of the final chamber extending from 

 the imibilicus about half the distance to the periphery, 

 with a few small accessory pores in the ventral face 

 of the final chamber. 



Remarks: Sestronophora, new genus, is similar to 

 Eponides Montfort but differs in having the umbilical 

 area covered by a series of plates pierced by pores and 

 in having supplementary openings on the umbilical 

 side of the final chamber. It is similar to Poroeponides 

 Cushman in having a few rounded openings on the 

 umbilical side of the final chamber, but differs in 

 possessing the complex perforated umbilical plates. 



Sestronophora amoldi Loeblich and Tappan, new species 

 Plate 73, Figure 5 



Pulvinulina punclulata (d'Orbigny), Baqg (not Rotalia (Rolalie) 

 punclulata d'Orbigny, 1826), U. S. Geol. Survey Bull. 513, 

 p. 86, pi. 25, figs. 6-9, 1912. 



Test free, large, trochospiral, strongly convex on 

 spiral side, umbilical side flattened and broadly umbili- 

 cate, periphery acute, keeled; 2% whorls visible on spiral 

 side, with chambers of greater breadth than height and 

 increasing in proportionate breadth as added; some- 

 what overlapping at the periphery, only the five to six 

 chambers of the final whorl visible on the umbilical 

 side, with the final chamber occupying about one-third 

 of the area, umbilicus occupying about one-third the 

 diameter of the test, and covered by a series of plates 

 arising at the inner margin of each chamber and 

 pierced by six or more relatively large openings, with 

 additional openings left around the margins of the sieve 

 plate, all openings connecting with the cavity beneath 

 the plates and laterally into the chamber cavities also; 

 sutunres distinct, thickened, depressed, gently curved, 

 strongly inclined backwards at the periphery on the 

 spiral side, nearly radial and more strongly depressed 

 on the umbilical side; wall calcareous, finely perforate, 

 surface lightly sculptured in the early portion on the 

 spiral side, smooth on the umbilical side; aperture a low 

 slit-like interiomarginal opening extending from the 

 umbilicus about K the distance to the periphery, with 

 from five to eight small supplementary openings in the 

 face of the final chamber. 



Greatest diameter of holotype 2.05 mm., thickness 

 0.94 mm. Paratypes range from 1.72 to 2.39 mm. in 

 diameter. 



