128 



UNITED STATES NATIONAL MUSEUM BULLETIN 215 



(see Bettenstaedt, 1949, p. 156). We have no very- 

 definite evidence as to the temperature of the sea in 

 Danian time (see Lowenstam and Epstein, 1954, pp. 

 244, 246). If one keeps these difficulties in mind, the 

 correlation of the type Danian with what Grimsdale 

 (1951, fig. 1) terms the "? Danian" of the Middle East 

 and the "Paleocene — Lower and Upper Midway" of 

 the Gulf of Mexico-Caribbean area can be made with 

 a fair degree of accuracy. Bettenstaedt and Wicher's 

 subdivision of the Danian-Montian into Danian I and 

 Danian II is undoubtedly practicable for the Tethys 

 area but can hardly be applied to Denmark-Sweden 

 or for that matter even to southern Belgium, which 

 is the type area of the Montian. The present writer 

 therefore favors a unification of the Danian and the 

 Montian into one stage. 



Acknowledgments 



The writer wishes to thank the Danish State Re- 

 search Foundation for having defrayed the cost of the 



preparation of the material and of the drafting of the 

 illustrations. Gratitude is also expressed to the Danish 

 State Research Foundation, the Rask-Orsted Founda- 

 tion, the Garlsberg Foundation and the University of 

 Copenhagen for having made possible a visit to the 

 United States National Musevma in Washington, where 

 type specimens were examined. The writer is happy 

 to acknowledge a debt to Alfred R. Loeblich, Jr., and 

 Helen Tappan Loeblich for much help, advice, and 

 hospitality; and to O. L. Bandy, P. Bronnimann, 

 J. G. Carlsson, C. Drooger, Brooks F. Ellis, H. Hagn, 

 Philip Morey, Grover E. Murray, A. Norvang, the late 

 H. J. Plummer, A. Rosenkrantz, and J. Wind for 

 material for comparison. Miss Gimni Jorgensen pre- 

 pared the drawings of the Foraminifera with her usual 

 skill and care. 



Figured hypotypes are deposited in the U. S. National 

 Museum collections, Washington, D. C. Additional 

 hypotypes from all samples are in the Miaeralogisk- 

 Geologisk Museum, Copenhagen, Denmark. 



Systematic Descriptions 



Clobigerina daubjergensis Bronnimann 

 Plate 30, Figures 1-2 



Globigerina daubjergensis Bbonnimann, Eclog. Geol. Helvetiae, 



vol. 45, No. 2, p. 340, fig. 1, 1953. 

 7 Globigerina daubjergensis Reichel, Eclog. Geol. Helvetiae, 



vol. 45, No. 2, p. 344, fig. 1, h, i, j, 1, 1953. 

 7 Globigerina triloculinoides Plummer, Brotzen, Sveriges Geol. 



Undersokning, ser. C, No. 493, pp. 89-90, pi. 17, fig. 2, 1948. 



Remarks: This species occurs throughout the Danian 

 stage of Scandinavia but is particularly abimdant in the 

 upper part, where it commonly dominates the plank- 

 tonic fauna (text-fig. 24). Three topotypes, kindly 

 presented by P. Bronnimann, permitted an accurate 

 identification of this somewhat variable but nevertheless 

 distinct species. The constant characters of the species 

 are (1) the finely spinose wall surface, (2) the trochoid 

 early chambers, (3) the small and shallow mnbilicus, 

 and (4) the small subcircular aperture which is not 

 surrounded by a lip and which opens into the umbilicus. 

 Two main morphological types have been observed, 

 one of them having a trochoid spire and, in the last 

 volution, 4 subglobular chambers which increase gradu- 

 ally in size; the other, a low spire and 3 to 3)^ rapidly 

 increasing chambers in the last volution. The low 

 spire is commonly produced by an involution of the 

 trochoid early chambers or by a rotation of the axis 

 of the test dm-ing growth. In the material at hand (a 

 few hundred specimens), the two types gi-ade imper- 

 ceptly into each other, and it has not been possible to 

 detect any pattern in their stratigraphic distribution 

 within the type Danian. 



Small accessory apertures commonly occur along the 

 sutures of the final chamber, but the writer has never- 

 theless refrained from referring the species to the 

 (probably polyphyletic) genus Globigerinoides. 



The occurence of G. daubjergensis in the Midway 

 group of the Gulf Coastal Plain has been mentioned 

 above. It may be added that in the Mexia clay member 

 only small trochoid specimens occur, while in the other 

 samples large specimens with inflated end chambers are 

 also present. 



Coiling ratio: Zone of Tylocidaris briinnichi: 

 Fakse, 56. percent dextral (±5.7). Zone of T. vexili- 

 jera: Ostra Torp, south Sweden, sample 1 (see text- 

 fig. 24), 52.7 percent dextral (±5.2); same locality, 

 sample 2, 55. percent dextral ±5.8); same locality, 

 exact level unknown, 40.9 percent dextral (±4.7). 



Dimensions: The specimens range in greatest diam- 

 eter of the test as follows: Basal Danian (Bogelimd and 

 Stevns Klint), 0.11-0.12 mm.; zone of T. odumi (Stevns 

 Klint), 0.21 mm.; zone of T. abUdgaardi (Stevns Klint), 

 0.19-0.32 mm.; zone of T. brunniehi_(Fak&e), 0.19-0.27 

 mm.; zone of T. vexilifera (Torp, Ostra Torp), 0.17- 

 0.26 mm. 



Globigerina paeudobuUoides Plummer 



Plate 30, Figures 6-8 



Globigerina pseudobulloides, Plummer, Univ. Texas Bull. 2644, 

 pp. 133-134; pi. 8, figs. 9a-c, 1926. 



Remarks: The specimens from the Danskekalk 

 formation have been compared with a large number of 

 specimens of typical G. pseudobulloides (some of them 

 identified by H. J. Plummer) from various parts of the 

 Midway group of the Gulf Coastal Plain. Although the 

 Danish specimens faU within theu' range of variation, 

 they differ so much from the majority of the topotype 

 specimens that it is considered desirable to add the 

 following partial description: 



Spiral side flattened, initial whorl either slightly 

 depressed or somewhat convex. Umbilical side strongly 



