Within the population of morphotypes referable to the writer's new taxon there is considerable variation of the degree to which the chambers are individually inflated. Thus, reference to the paratype figured on pl. 150, fig. 9, shows a form in which the chambers are not so greatly inflated as in the holotypic specimen. The paratypes figured on pl. 150, figs. 5 and 6, show the general appearance of the dorsal and ventral aspects of morphotypes included in the taxon whilst the other paratype figured on this plate (fig, 7) shows a slightly greater extension of the aperture towards the dorsal side than as seen in the holotypic specimen illustrated on pl. 150, fig. 8. The four paratypes and the holotype illustrated on pl. 150, figs. 5-9, illustrate the range of variation normally encountered for the representative morpho types of the new taxon griffinae in relationship to those included in Hastigerina? bolivariana (Petters) [Globigeritia wilsoni bolivariana, 1954] as figured on the same plate (Blow, 1979, loc. cit., figs. 1-4).

"In the holotype and paratypes of G. (T.) griffinae Blow, 1979 discussed above, the mural-pores are small and do not open into large pore-pits with well marked inter-pore ridges. However, on pl. 153, fig. 7, pl. 162, figs. 8 and 9, and pl. 165, figs. 1-3, other paratypes are illustrated in which the mural-pores are quite large and do open into distinct pore-pits with distinct inter-pore ridges. Inspection of these other paratypes also shows that associated with these larger mural-pores and better developed pore-pits is a somewhat tighter coiling-mode and a consequently smaller, almost closed, umbilicus. In addition to this, the second group of paratypes show more pronounced apertural rims. Thus the paratypes and holotype on pl. 150, figs. 5-9 from Zone P.9 show many features of the wall and general chamber shape in com mon with Hastigerina? bolivariana (Petters), but the paratypes from Zone P.10 have a more coarsely cancellate wall surface, a somewhat tighter coiling-mode and chambers which are more closely appressed as compared to the holotype and paratypes from Zone P.9. Nevertheless, it will be noted (cf. pl. 165, fig. I, for example) that the morphotypes from Zone P.10 do show ontogenetic variation in pore-size and pore-density combined with ontogenetically controlled increase in size of the pore-pits. Furthermore, it is not possible to unambiguously place a boundary between those forms with the more open umbilicus and those forms with the more-or-less completely closed umbilicus, neither is it possible to divide the morphotypes on a consistent and unambiguous basis purely on the degree of development of the apertural rim thickening. Consequently, the writer does not consider, in the light of present knowledge, that it is possible to subdivide the morphogroup taxonomically, either on the single or combined expression of the various characters discussed above; all the morphotypes are included in the taxon Globorotalia (T.) griffinae Blow, 1979. However, it must be noted that the increasing coarseness of the wall surface, the increasing tightness of the coiling-mode and the increasing appression of the chambers are features which are acquired in a sequence with time-significance. Thus, the later forms (which range Zone P.10 to Zone P.11) appear to show no gradation to the forms included in Hastigerina? bolivariana (Petters) whilst the earlier forms (cf. p1. 150, figs. 5-9) frequently show gradation with Petters' taxon over the interval of Zone P.9 to Zone P.10 (?earlier part only).

In the writer's view, if Globorotalia (Turborotalia) and Hastigerina are, eventually, used as supraspecific groups to include only the forms without portical structures, then griffinae and bolivariana should be considered as referable to a new genus (cf. Blow, 1979, op. cit. pp. 1046, 1177). The writer would also consider that griffinae and bolivariana could be united in one single new genus regardless of the differences in coiling-mode although they remain specifically distinct. In this regard it would seem that, for phyletic reasons, griffinae and bolivariana should be further considered, in future work, as being placed with the Clavigerinella taxa in a new supra-generic group but with the latter taxa removed from the Hastigerininae.

Some authors appear to have regarded Globigerina wilsoni Cole as being a morpho type either similar to those forms called griffinae Blow, 1979, or to those forms called bolivariana (Petters) in this work. However, Bolli's (1957, /0c. cit.) specimens referred to `bolivariana' are considered as being referable to G. (T.) increbescens (Bandy) [Globigerina increbescens, 1949] and it would seem that `Globigerina wil soni Cole' of Weiss (1955, /cm. cit.) is also either referable to increbescens (Bandy) or opirna nana Bolli. Cole's (see catalogue sheet) record of the holotype of Globigerina wilsoni is to a small morphotype of 0.24 mm maximum diameter. There are several small morphotypes in samples from the Guayabal formation which would reasonably fit Cole's description for wilsoni but it is more than possible, at least, that Cole's taxon is a prior synonym for Globigerina increbescens Bandy, 1949.

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