46 



UNITED STATES NATIONAL MtJSEUM BTILLETIN 216 



family Globorotaliidae, probably Botalipora. The 

 minor differences in proportions of these two openings 

 shown in various "genera" in his text-fig. 1 are certainly 

 of not more than specific value. 



As shown in the present paper, and recognized by 

 most authorities on the planktonic genera, true Gloho- 

 truncana has an lunbilical primary aperture. In well 

 preserved specimens this is always covered by the mn- 

 bilical tegilla, the only connection to the outside being 

 through the infralaminal accessory apertures, which 

 open beneath the tegiUa, not directly into the chambers 

 themselves. 



Hofker selected Rosalina marginata Reuss as type 

 species for his genus. In the original description of the 

 species (a true Glohotruncana), Reuss (1845) mentioned 

 the perpendicularly truncate outer margin (typical of 

 double-keeled forms) and broad umbilicus. The origi- 

 nal figures are small and somewhat generalized. How- 

 ever, that of Reuss' fig. 68, pi. 13, from the Planermergel 

 (Tvu'onian) is here designated as lectotype, as it shows 

 the open umbilicus and other cha,racters mentioned in 

 the original description. Better figures are given by 

 Cushman (1936, pi. 62, fig. 1), of a specimen in the Reuss 

 collection at Cambridge, which is from the original 

 locality. Hagn and Zeil (1954, pi. 2, fig. 4) showed 

 very similar specimens from the Turonian of the 

 Bavarian Alps. 



In addition to the lectotype, Reuss also figured as 

 Bosalina marginata a specimen (pi. 8, fig. 74) from the 

 lower Planer (Cenomanian) which differed from the 

 written description in lacking an open mnbiHcus. 

 Because of this character and the apparently extra- 

 umbilical apertm-e, this specimen is probably a species 

 of Praeglobotruncana or Botalipora. The geologic 

 occurrence supports this assumption, as true Gloho- 

 truncana does not occur in the Cenomanian, whereas 

 both Praeglobotruncana and Botalipora do appear there. 



Completely disregarding Reuss' original description 

 of the species (only the later publication of Reuss, 

 1854, was cited by Hofker) as well as the later descrip- 

 tions and figures of the species, Hofker figured as 

 Marginotruncana marginata (Reuss) a single-keeled 

 form with an extramubilical aperture. Hofker com- 

 mented with regard to his text-fig. 6 that itsome what 

 resembled Botalipora, and also stated (p. 323) that no 

 typical M. marginata occurs in the Cenomanian- 

 Turonian of southern Germany, although it was origi- 

 nally described from Bohemia and has since been re- 

 corded from Bavaria by Hagn and Zeil (1954). Hofker 

 stated (p. 324) that Hagn's form was not true marginata 



(he credited the 1954 publication solely to Hagn, 

 although it was under the joint authorship of Hagn 

 and ZeU), yet Hagn and Zeil's specimens of a double- 

 keeled Glohotruncana more closely resemble the original 

 figm-es and description of Reuss, and are geographically 

 closer to the type area, than those of Hofker. 



From the illustrations given, it is probable that Hof- 

 ker identified as the species marginata, specimens which 

 are actually Fraeglohotruncana, although his citation of 

 Bosalina marginata Reuss as type species, places the 

 genus Marginotruncana as a junior synonym of Gloho- 

 truncana. 



In addition to the type species, Hofker also included 

 in Marginotruncana the following species of typical 

 Glohotruncana: Bosalina stuarti Lapparent, Glohotrun- 

 cana glohigerinoides Brotzen, Marginotruncana para- 

 ventricosa Hofker (which included G. ventricosa oj 

 Brotzen, not White) and Marginotruncana pauperata 

 Hofker (including G. marginata of Visser, not Reuss). 

 He also included other totally unrelated species, such 

 as G. intermedia Bolli (an Ahathomphalus), G. citae 

 BoUi (a Fraeglohotruncana), G. stephani var. turhinata 

 Reichel (a variety of the type species of Botundina, a 

 junior synonym of Praeglobotruncana), G. ticinensis 

 Gandolfi (a Botalipora previously placed in Thalmanni- 

 nella, jimior synonym of Botalipora), and G. appenninica 

 Renz (also a Botalipora). He thus included in his 

 Marginotruncana, species with the distinctive characters 

 of the genera Praeglobotruncana Bermudez, 1952 (and 

 its synonym Botundina Subbotina, 1953), Botalipora 

 Brotzen, 1942 (and its synonym Tfoalmanninella Sigal, 

 1948), which belong to the family Globorotaliidae, and 

 the genera Glohotruncana Cushman, 1927 (and its 

 synonym Bosalinella Marie, 1941) and Ahathomphalus 

 Bolli, Loeblich and Tappan, which belong to the 

 family Globotruncanidae. All but the last of these 

 generic names preoccupy that of Hofker, if aU were 

 congeneric. 



Types and occurrence: Holotype of Pvlvinvlina 

 area Cushman (type species of Glohotruncana) (Cush- 

 man Coll. 5078) from the Mendez shale, near Huiches, 

 Hacienda El Lim6n, San Luis PotosI, Mexico. 



Figured hypotypes of Glohotruncana area Cushman 

 (USNM P4242 a-e) from Navarro (Corsicana marl), 

 branch of Mustang Creek, 1.0 miles WSW of Noack, 

 900 feet downstream (south) from road and 0.2 mile 

 southwest of Christ Evangelical Lutheran Church, 

 Williamson County, Texas. Collected by Noel Brown. 



Range: Turonian to Maestrichtian. 



