188 



UNITED STATES NATIONAL MUSEUM BULLETIN 215 



Mountain limestone, in a limestone sink, K mile north 

 of Salt Momitain in the NWKNW/4, Sec. 34, T. 6 N., 

 K. 2 E., Clarke Co., Alabama. Collected by H. T. and 

 A. K. Loeblich, Jr. 



Globorotalia compressa (Plummer) 



Plates 40, Figures 6a-c; 41, Figures 5a-c; 42, Figures 

 5a-c; 44, Figures 9a-10c 



Globigerina compressa Plummer, Univ. Texas Bull. 2644, p. 135, 



pi. 8, figs, lla-c, 1926. 

 Globorotalia ehrenbergi Bolli, U. S. Nat. Mus. BuU. 215, p. 77, 



pi. 20, figs. 18-20, 1957. 



Test free, trochospiral, compressed, umbilical side 

 with small deep umbilicus, periphery subacute, peri- 

 pheral outline lobulate; chambers moderately inflated, 

 more so on the umbilical side, enlarging rapidly in size 

 as added, of nearly equal breadth and height, arranged 

 in about 2 whorls, commonly 5 occur in the final whorl ; 

 sutures distinct, gently curved, slightly depressed; 

 wall calcareous, distinctly perforate, surface smooth; 

 aperttire interiomarginal, extraumbilical-umbihcal, an 

 arched opening extending nearly to the periphery, and 

 bordered above with a narrow Hp. 



Hypotypes range in diameter from 0.28 to 0.38 mm. 



Remarks: This species has been misinterpreted by 

 some workers. Bronnimann (1952, p. 25, pi. 12, figs. 

 19-24) referred to 6. compressa specimens with a more 

 angular or keeled periphery, rapid increase in chamber 

 size, relatively large final chamber, and larger test; 

 these latter forms are here referred to Globorotalia 

 elongata Glaessner. The holotype of Globorotalia ehren- 

 bergi BoUi is identical in appearance to metatypes of 

 G. compressa Plummer, and this specific name is there- 

 fore considered a synonym. 



Typical G. compressa (as shown by metatypes and 

 topotypes) is very similar to Globigerina pseudobulloides 

 Plummer, differing in being smaller and with a some- 

 what more angular peripheral margin (compressed) and 

 smooth, very finely perforate wall instead of the more 

 coarsely perforate and pitted wall of G. pseudobulloides. 



Globorotalia imitata Subbotina is also similar to the 

 present species but has a rounded rather than subacute 

 periphery, and a more flattened spiral side, more curved 

 sutures and lower chambers. 



Types and occurrence : Figured hypotype (USNM 

 P5716) from the Danian calcarenite at Ostratorp, 

 Skine, Sweden. Collected by J. C. Troelsen. 



Figured hypotypes (USNM P5717a,b) from the WUls 

 Point formation, in road cut near top of hUl on the 

 Corsicana-Navarro road just south of the junction with 

 the Mildred road, Navarro County, Texas. Collected 

 by A. E. Loeblich, Jr. 



Figmed hypotype (USNM P5718) from the McBryde 

 limestone member of the Clayton formation, in bed of 

 Rock Creek, 0.8 mile south of junction of Alabama 

 Highways 28 and 10, on Highway 10, Wilcox County, 

 Alabama. Collected by A. R. Loeblich, Jr. 



Figured hypotype (USNM P5719) from the type 

 locality of the Brightseat formation, 1 mile west-south- 



west of Brightseat and 0.2 mile south of Sheriff Road, 

 Prince Georges County, Maryland. Collected by A. R. 

 Loeblich, Jr., and Richard A. Page. 



Globorotalia convexa Subbotina 



Plates 48, Figures 4a-c; 50, Figures 7a-c; 53, Figures 6a-8c; 

 57, Figures 5a-6c; 61, Figures 4a-c; 63, Figures 4a-c 



Globorotalia convexa Subbotina, Trudy Vses. Neft. Naukno- 

 Issledov. Geol.-Razved. Inst., new ser., vol. 76, p. 209, pi. 17, 

 figs. 2a-3c, 1953. 



Test free, ovate in outline, trochospiraUy coiled, 

 inflated, peripheral margin rounded, peripheral outline 

 slightly lobulate; chambers gradually enlarging, all 

 whorls visible on the flattened spiral side, only the 4 to 

 6 chambers of the final whorl visible around the nearly 

 closed umbilicus on the umbilical side; sutures some- 

 what indistinct, strongly curved backwards on the spiral 

 side, radial on the umbilical side; wall calcareous, per- 

 forate, entire surface spinose; aperture interiomarginal, 

 extraumbilical-umbilical, a low arched opening extend- 

 ing about halfway to the periphery, with a narrow lip 

 above. 



Hypotypes range in greatest diameter from 0.23 to 

 0.30 mm. and in thickness from 0.13 to 0.23 mm. 



Remarks: Globorotalia convexa Subbotina is similar 

 to Globigerina mckannai White in its surface textiu-e and 

 number of chambers per whorl, but differs in the smaller 

 size, more strongly curved but somewhat obscure and 

 less incised sutures, more broadly rounded periphery, 

 and nearly closed umbilicus. 



It differs from Globorotalia albeari Cushman and Ber- 

 mudez in being smaller, in having fewer chambers per 

 whorl, a more rounded periphery, less distinct sutures, 

 flatter spiral side, and more spinose surface. 



It is similar in appearance to Globorotalia broeder- 

 manni Cushman and Bermudez from the lower Eocene 

 CapdevUa formation of Cuba, but differs in being only 

 about % as large and in having a more closed umbilicus, 

 and a lower and much smaller apertural opening. The 

 present species is probably ancestral to the lower 

 Eocene species. 



Types and occurrence : Figured hypotypes (USNM 

 P5129a-c) from the Vincentown formation, north bluff 

 of Rancocas Creek, 0.3 to 0.5 miles north of Vincen- 

 town, Biu-lington County, New Jersey. Collected by 

 A. R. Loeblich, Jr., and Norman Sohl. 



Figmed hypotype (USNM P5845) from the Horners- 

 town formation, north bank of Shingle Run, a tributary 

 to Crosswicks Creek, 1.0 mile north of New Egypt, 

 Monmouth County, New Jersey. Collected by A. R. 

 Loeblich, Jr., and Norman Sohl. 



Figured hypotypes (USNM P5846a, b) from the 

 Aquia formation, 14-16 feet above base of exposure, 

 west bank of Potomac River, near mouth of Aquia 

 Creek, S. 10° E. of Brent Point on U. S. Geological Sur- 

 vey Nanjemoy Md.-Va. Quadrangle, 1:62,500, 1913, 

 reprinted 1945. Collected by A. R. Loeblich, Jr., and 

 Richard A. Page. 



Figured hypotype (USNM P5847) from the Salt 



