STUDIES m FORAMINIFERA 



147 



or more or less depressed and are more inflated toward 

 the axis of the test. In Bolivinita the chambers are 

 pyriform in section, but have the more inflated portion 

 at the external side of the test. This gives rise to flat 

 or even concave broader faces of the test, and the 

 strongly oblique chambers allow the lateral fusion of the 

 limbate frontal sutures to form four vertical costae or 

 lamellae. This character is present in different genera 

 (Boliviniiella, Eouvigerina plummerae) which are easily 

 distinguishable by such other morphological elements 

 as the aperture and the chamber arrangement. 



For these reasons, an invalidation of the name Boli- 

 vinita seems at least premature, and it is here recognized 

 as a valid genus. 



Genus Tappanina Montanaro Gallitelli, 1955 



Plate 33, Figure 21 



Tappanina Montanaro Gallitelli, Mem. Accad. Sci. Lett. 

 Arti Modena, eer. 5, vol. 13, p. 18, 1955. 



Type species: Bolivinita selmensis Cushman, 1933, 

 Upper Cretaceous Selma chalk, from New Corinth high- 

 way, 13.5 miles South of Selmer, McNairy County, 

 Tennessee. 



Diagnosis: Test biserial, rectangular or rhomboidal 

 or deformed in transverse section. Chambers depressed, 

 cuneiform, apparently concave on the broad sides, more 

 or less inflated laterally, with a well developed and some- 

 times fringed or lamellar carina which is horizontal or 

 arched on the lateral margin then deflected and parallel- 

 ing the long axis of the chambers. Sutures thin, de- 

 pressed, straight or arched. Wall calcareous, finely 

 perforate. Surface appears rough when carinae are 

 strongly developed. Aperture narrow, elongate, at the 

 center of the base of the last chamber. 



Discussion: The cuneiform shape of the adult cham- 

 bers, with lateraUy subhorizontal or arched carinae, the 

 deflection of the carinae on the broader faces, giving a 

 rectangular transverse section to the test, and the inde- 

 pendence of the carinae from the sutures are constant 

 characters of this genus. Variable characters are the 

 lateral convexity of the chambers, the development of 

 the carinae and the more or less angular deflection at 

 the beginning of the broader faces, and the deformation 

 of the test in section from rectangular to rhomboidal or 

 eUiptical. 



The group of forms allied to the type species have 

 fundamentally different characters than do either Boli- 

 vinita Cushman or BoliviniteUa Marie. Distinctive ele- 

 ments pecifliar to the genus Tappanina are the presence 

 of strong horizontal carinae, the narrow and deep su- 

 tures, the degeneration of the fouir axial lameUar sutural 

 costae, characteristic of Bolivinita and Boliviniiella, into 

 discontinuous thickenings and the character of the 

 aperture. 



Neither Cushman nor the later authors who examined 

 specimens of this widespread species {Tappanina sel- 

 mensis has also been found in the Upper Cretaceous and 

 Paleocene of Europe) recognized the actual distinction 



between the lateral thin sutures and the strongly de- 

 veloped horizontal arched carinae, which are relatively 

 close to the preceding suture, and which give the tecti- 

 form appearance to the test. 



The description of Bolivinita selmensis given by 

 Cushman (1946, p. 114) is as follows: "Test minute, 

 gently tapering from the subacute initial end, broad 

 faces distinctly concave, the narrow sides strongly 

 convex; chambers distinct, increasing gradually in size 

 as added; sutures distinct, somewhat limbate; wall 

 smooth, very finely perforate, translucent, especially 

 in the middle of the chambers on the flattened faces; 

 aperture narrow, at the inner margin of the last-formed 

 chamber." 



An analogous description was given for the very 

 similar Bolivinita costifera Cushman (1946, p. 115): 

 "Test small, about twice as long as broad, gradually 

 tapering from the subacute initial end to the greatest 

 breadth slightly above the middle, thence tapering 

 slightly to the apertural end, periphery broadly round- 

 ed, strongly serrate in front view, in transverse section 

 somewhat rhomboid, broader faces flattened or con- 

 cave; chambers very distinct, increasing gradually in 

 size as added, earlier chambers flattened and com- 

 pressed, later chambers concave on the broader faces, 

 and convex on the periphery, greatly increasing in 

 thickness; sutures distinct, slightly curved in the early 

 stages, more strongly so in the adult, slightly limbate; 

 wall smooth and polished, except for the basal angle of 

 the chamber in the adult, which has a sharp angle that 

 may develop into a raised costa-like ridge; aperture 

 narrow, elongate, at the base of the inner margin of the 

 apertural face." 



The holotype of Tappanina selmensis is here refigured. 

 The holotype of Eouvigerina excavata Cushman con- 

 sists of a specimen of T. selmensis with the last chamber 

 broken and thus simulating a neck. This confirms the 

 doubt of Brotzen (1948) about the validity of the 

 species excavata. Only a "paratype" of the species 

 selmensis, figured by Cushman and refigured by 

 Brotzen (1948, text fig. 16, specimen on the left) is 

 perhaps a true Bolivinita, characterized by the slender 

 test and the typical sutures and sculpture, but the 

 absence of other specimens compels a further investi- 

 gation as to the existence of a toothplate. 



Brotzen proposed a list of synonyms for selmensis: 

 Bolivinita crawjordensis Jennings, B. exigiui Glaessner, 

 B. costerifera (read costifera) Cushman. However, after 

 examining many paratypes and hypotypes from the 

 Kemp Clay, the writer believes Tappanina costifera to 

 be a valid form, although closely related to the type 

 species. B. exigua Glaessner from the Upper Cre- 

 taceous of the Caucasus appears from the figures and 

 descriptions to be a synonym of T. selmensis. B. 

 crawfordenis Jennings, from the lower Eocene of New 

 Jersey, cannot be satisfactorily compared with T. 

 selmensis because of the insuflicient description and 

 figure of the former. 



In addition to the holotype of Tappanina selmensis 

 (Cushman), the writer (Montanaro Gallitelli, 1956, 



