136 



tnsriTED STATES NATIONAL MUSEinVI BULLETIN 215 



(1) triserial (subfamily Guembelitriinae) 



(a) constantly triserial Guembelitria 



(b) with proliferation Guembelitriella 



(2) biserial or planispiral (subfamily Heterohelicinae) 



(a) with average proportion of thickness to breadth 1:2 



Heterohelix 



Pseudoguembelina 



Tuhitextularia 



(b) proliferation in the adult stage, average proportion 



of thickness to breadth= 1:1 Racemiguembelina 



(c) frequently planispiral in early stage then prolifer- 



ated, average proportion of thickness to breadth 



1 :4 to 1 :7 Guhlerina 



Planoglobulina 



(d) planispiral and biserial, average proportion of 



thickness to breadth 1.5:1 to 4:1 



Pseudotextularia 



Bolimnella, Plectofrondicularia, and Amphimorphina 

 have in common an early biserial stage (continued to 

 the matTire stage in Bolimnella), absence of a columellar 

 process, aperture reduced by tuberculations or even 

 subcribrate. 



The subfamily Plectofrondicuilariinae Cushman can 

 be maintained, but it has no relationship to the Hetero- 

 helicidae as presently emended. We do not know how 

 closely the apertural character is concerned with con- 

 ditions of life, but the shape of the test, the biserial 

 early arrangement of the generally flat chambers, the 

 peculiar reduction of the lumen in the apertiu-e, and 

 the lack of a colimiellar process have led us to here 

 consider the former subfamily Plectofrondiculariinae 

 as a distinct family, the Plectofrondiculariidae. 



Bolivinita Cushman, Bolimnoides Cushman, and 

 Tappanina Montanaro GaUitelli are interrelated by 

 having the test biserial, costate or carinate; chambers 

 not globular; aperture basal, central, narrow. Colu- 

 mellar processes are sinuous and discontinuous. Boli- 

 vinitella Marie is only an example of convergence with 

 Bolivinita, and must be separated from this quite 



dififerent group, as is discussed more fuUy below. These 

 three genera belong to the subfamily Bolivinitinae. 



The subfamily Eouvigerininae (type genus Eouvi- 

 gerina Cushman) is placed within the family Bulimi- 

 nidae after the subfamily Bolivinitinae. The original 

 description of Eouvigerina is also emended, with de- 

 scription of an internal columeUar process. 



Siphogenerinoides Cushman is initially biserial, not 

 triserial as formerly described, and must be placed 

 only provisionally near the Eouvigerininae until more 

 information is available as to the genetic value and the 

 ratio of variability of the columellar process. Also, its 

 placement in the family Plectofrondiculariidae seems 

 at present at least premature because of the substan- 

 tially different structiu-e of the columeUar process. 

 The name Siphogenerinoides is not exact from the point 

 of view of the character it recalls, as the columeUar 

 process is not a siphon but a large discontinuous spout. 



Zeauvigerina Finlay, Trachelinella Montanaro GaUi- 

 teUi, and Bolivinitella Marie are biserial, with apertural 

 neck, without columeUar process, and are stUl incertae 

 sedis, perhaps near the Bolivininae, from which they 

 are distinguished by the terminal aperture and neck. 



Of the Tertiary Tosaia Takayanagi only three para- 

 types were examined. It is possible that there is a 

 trochoid initial stage, but this requires further investi- 

 gations. All the specimens seen have a quite bulimin- 

 oid aperture. There is no relationship to Guembelitria 

 or other true Heterohelicidae; on the other hand a rela- 

 tionship with the Buliminidae seems quite probable. 



Pseudouvigerina Cushman must be placed unques- 

 tionably in the Uvigerininae, as was done by Glaessner 

 (1945). It has a triserial test, terminal aperture with 

 neck and lip, columeUar process, and longitudinal orna- 

 mentation. The genus is closely related to Angulo- 

 gerina. 



Systematic Descriptions 



Family Heterohelicidae Cushman, 1927, emended 



Test calcareous, perforate; chambers inflated, spheri- 

 cal, globular or reniform; early stage either planispiral, 

 biserial, or triserial, not trochoid; serial reductions or 

 proliferations are occasionaUy present; aperture rela- 

 tively large, simple and basal in biserial or triserial 

 forms, terminal only in accelerated uniserial forms. 

 ColumeUar processes absent. 



Subfamily Guembelitriinae Montanaro GaUiteUi, 

 new subfamily 



Test triserial; chambers globular; aperture basal, 

 arched, simple. 



Genus Guembelitria Cushman, 1933 



Plate 31, Figures 1, 2 



GUmbelitria Ctjshman, Contr. Cushman Lab. Foram. Res., vol. 

 9, p. 37, 1933. 



Type species: Guembelitria cretacea Cushman, 1933, 



Upper Cretaceous Navarro (Maestrichtian), from pit of 

 Seguin Brick and Tile Company, 0.8 mile south of 

 McQueeny Station, Guadelupe County, Texas. 



Diagnosis: Test calcareous, triserial. Chambers 

 generally globular, more or less regularly aligned in 

 three series throughout development. Aperture basal, 

 arched, simple. 



Discussion : An examination of aU the specimens of 

 Guembelitria in the U. S. National Museum shows that 

 neither initial coU nor initial biserial stage are present. 

 Only a single specimen is dubious, but even when im- 

 mersed in anise oil it does not give the appearance of a 

 true biserial initial stage. 



On the other hand, specimens where the alignment of 

 the three series of chambers is irregular are not rare. 



Guembelitria vivans Cushman, a living form, is not a 

 true Guembelitria, although triserial and with globular 

 chambers. The aperture is extremely narrow, elon- 

 gated perpendicular to the suture, and turned inwards, 

 as in certain Buliminidae (see fig. 2). Guembelitria 



