140 



tnsriTED STATES NATIONAL MUSEUM BULLETIN 215 



P. excolata (Cushman)'TandTP. palpebra Bronnimann 

 and Brown, the accessory apertures are present from 

 the very first stages, are connected with a peculiar 

 feature of the chambers, and, finally, have a quite 

 different appearance from the accessory apertures we 

 observe occasionally ia other Heterohelicidae. A 

 specimen of P. costulata was chosen to show the peculi- 

 arity of this character. The reniform chambers 

 become constricted near the axial area, then extend 

 laterally in two lobes, which are tubuliform when weU 

 developed, and curved to meet the lower chambers. 

 When the lobes are small, one may observe (fig. 22) 

 that they originate from a conspicuous extension of 

 the aperture, with two more or less marked constric- 

 tions near the two lateral extremities of the aperture. 

 In such a situation, the chambers lose their original 

 globular appearance. The morphological transition 

 from globular to reniform to lobate chambers may be 

 observed in the populations of HeUrohelix {Guembelina) 

 glohulosa and H. planata, and H. pseudotessera i=H. 

 pulchra (Brotzen), 1936; see Montanaro GaUitelli, 

 1955b, p. 188). Consequently, the genus Pseudoguem- 

 belina Bronnimann and Brown is considered to be a 

 vaUd genus, but is restricted to include only those 

 forms with a strong modification in the shape of the 

 terminal basal part of the chambers and of the aperture, 

 which give rise to peculiar accessory apertures, differ- 

 ing in their origin from the accessory apertures occasion- 

 ally found in other species and genera of the Hetero- 

 helicidae. For this reason, P. striata and P. punctulata 

 are not considered to be typical Pseudoguembelina, but 

 are here considered to belong to Heterohelix. 



Bronnimann and Brown (1953, p. 153) stated that 

 "Textularia striata Ehrenberg is the only species of 

 Psevdogeumbelina n. gen. in which coUing has been 

 observed." The present study has shown that it 

 occurs also in P. excolata (Cushman), the type species 

 of the genus (fig. 23) . 



Genus GuLlerina Kikoine, 1948 



Plate 32, Figtjbes 1-9 



GubUrina KikoIne, Soc. G^ol. France, Bull., ser. S, vol. 18, fasc. 

 1-3, p. 26, 1948. 



Type species: Gublerina cuvillieri Kikoine, 1948 

 (= Ventilabrella omatissima Cushman and Chm-ch, 

 1930), Upper Cretaceous (Maestrichtian), from the 

 region of Orthez and to the south of Gan, northern edge 

 of the Pyrenees, France. 



Diagnosis: Test compressed, rapidly increasing in 

 breadth but not flabeUiform, presenting a fairly broad 

 triangular outline. Early stage frequently coiled; in 

 the later stage the chambers are arranged in two 

 diverging series, commonly widely separated by a 

 broad, nonseptate, incompletely divided or occasionally 

 bubbled central area which only finally becomes camer- 

 ate. Proliferation of chambers occurs at the top of 



the test, with 4-8 final bulbous chambers. Sutures 

 well developed, limbate, generally granulate on the 

 surface, sometimes strongly projecting. Wall calcar- 

 eous, surface opaque, rough, especially in the early 

 stage, except for the initial coU which is generally 

 smooth and transparent. Aperture not visible in the 

 pparatyes available. 



Discussion: Comparison of the holotype and para- 

 types of Ventilabrella omatissima Cushman and Church 

 with the topotypes of Gublerina cuvillieri, in the National 

 Museum collections, showed that the specific name 

 cuvillieri is also invalid as it is a synonym of Gublerina 

 omatissima (Cushman and Church) . The morphologic 

 characters of this genus brought out in this paper prove 

 its validity, although the genus must be somewhat 

 emended from the original description. Recognition 

 of these characters was made possible by etching away 

 in hydrochloric acid the external part of the wall in two 

 specimens of Gublerina cuvillieri {=G. omatissima). 



Thus, a coiled early stage may be present (fig. 3), 

 followed by the young biserial stage. The first two to 

 four pairs of chambers are overlapping, then the two 

 series of chambers become more and more divergent, 

 leaving a broad internal communication between the 

 chambers and the wide undivided central cavity (fig. 

 7). True internal chambers are not developed at 

 first in this central area, which becomes irregularly 

 more or less "bubbled" in appearance (fig. 4). The 

 granulated, suturelike median costae were dissolved at 

 the surface by hydrochloric acid in order to verify the 

 presence of a median series of chambers, but no internal 

 chambers were found to correspond with these super- 

 ficial costae (fig. 2). Another partially dissolved 

 specimen (fig. 1) and three complete specimens (figs. 

 5, 7, 3) show the sequence from a fiat, depressed, and 

 unoriamented central area to a subcostate to a final 

 bubbled one. In figure 4 granulated intermediate 

 costae and the final polycamerate stage can be seen. 



A specimen of Ventilabrella omatissima Cushman 

 and Church, similarly treated (figs. 6a, b), shows that 

 the two series of chambers openly communicate in the 

 central area, and that a third incomplete arched suture 

 appears in the central area, immediately below the 

 final proliferation. 



Ventilabrella decoratissima de Klasz is a Gublerina 

 with strongly developed granulated sutures, and a 

 biserial arrangement of chambers nearly to the top of 

 the test, which shows the usual final proliferation. 

 Paratypes of this species from the Santonian of Eisen- 

 arzt, Bavaria (de Klasz Coll.) show the Gublerina- 

 arrangement of the chambers and the surface sculpture 

 (fig. 8). 



The constant characters of Gublerina are, therefore, 

 the biserial arrangement of the chambers almost to the 

 top of the test, with the two gradually diverging series 

 separated by an intervening noncamerate cavity; and 

 the limbate sutures, frequently granulate on the surface, 



