TAXONOMIC REVISION OF FORAMINIFERA IN MILLETT COLLECTION 



119 



Millett Collection, is of the Trochamminina-type (see below), 

 we prefer, in our treatment of this species, to use Haplo- 

 phragmoides in inverted commas, until more is known about 

 canadensis. 



'Haplophragmoides' wilberti Andersen, 1953 



Figs 1.12, 16-21 



1899 Trochammina ochracea Williamson; Millett: 363, pi. 



5, figs 12a-c (non Williamson, 1858). 

 1953 Haplophragmoides wilberti Andersen: 21, pi. 4, figs 



7a,b. 

 1961 Haplophragmoides wilberti Andersen; Todd & Low: 



133; pi. 1, fig. 5. 

 1973 Haplophragmoides wilberti Andersen; Haynes: 



27-30, pi. 2, fig. 1; pi. 29, fig. 11; text-figs 5.3-7. 

 1977 Haplophragmoides wilberti Andersen; Zaninetti et 



al: pi. 1, figs 12,13. 

 1981 Trochammina sp., Cann & de Deckker: 668, pi. 2, 



figs 1-19. 

 1983 Haplophragmoides wilberti Andersen; Haman: 71; 



pi. 3, figs 14,15. 



Remarks. On re-examination. Milieu's (1899, pi. 5, figs 

 12a-c; reproduced here as Figs 1.12a-c) so-called Trocham- 

 mina ochracea proved to be a planispiral 'Haplophrag- 

 moides'. It is re-illustrated by SEM in Figs 16-18 and it 

 (BMNH no 1955.11.1.5003) clearly shows the same collapse 

 features as the original drawings. In addition to this speci- 

 men, we have illustrated for comparative purposes (Figs 

 19-21), another, somewhat less deformed specimen, from 

 Acupe, Brazil (BMNH no. ZF 5002). 



The coiling of Millett's species is planispiral, virtually 

 involute, with 7 or 8 chambers in the final whorl. The 

 aperture is a single interiomarginal equatorial slit with a 

 broad everted border. The intercameral sutures are incurved, 

 occasionally sinuous. We are placing it into the widespread 

 brackish form, 'H'. wilberti Andersen. Millett must have 

 regarded it as a Trochammina because of the incurved test 

 seen in edge view. 



Cann & de Deckker (1981, pi. 2, figs 1-19) illustrated from 

 ephemeral lakes adjacent to the Coorong Lagoon, South 

 Australia, a series of haplophragmoid forms, in part 

 deformed, which they called Trochammina sp. They are very 

 similar to T. ochracea sensu Millett and we have also placed 

 them in '//'. wilberti. 



Collapse features occur often in brackish foraminifera. The 

 overall consistency of the agglutinated phase, in particular its 

 thickness and cementation, seems to play a role. In the 

 deformed Millett material it appears that the agglutinated 

 phase is rather weakly developed. In non-deformed speci- 

 mens of '//'. wilberti, at our disposal, from brackish localities 

 in Nigeria and New Guinea, the wall structure was analysed 

 using high-resolution scanning electron microscopy of frac- 

 tured tests. It was found that the wall of these specimens is 

 made up of the organic phase (represented by thin inner and 

 outer sheets and material ('glue') between agglutinated ele- 

 ments), and the agglutinated phase. There were no perfora- 

 tions nor alveolar pseudopores present. This is the 

 characteristic Trochamminina-type wall. In these latter, non- 

 deformed specimens, the agglutinated phase appears to be 

 stronger, perhaps better cemented, than the Millett material 

 from the Malay Archipelago. 



Dimensions of figured specimens (MALAY SPECIMEN, 



BMNH no. 1955.11.1.5003). Maximum diameter — 490 urn; 

 axial height (thickness) — 125 \xxn. 



(BRAZILIAN SPECIMEN, BMNH no. ZF 5002). Maxi- 

 mum diameter — 340 um. 



Environment. According to Millett (1899; 363) this species 

 . . . 'has been observed only at Station 3'. It is a good 

 brackish water indicator and occurs in association with Trem- 

 atophragmoides bruneiensis at this locality. 



Genus PARATROCHAMMINA Bronnimann, 1979 



Type species. Paratrochammina madeirae Bronnimann, 

 1979 



Paratrochammina simplissima (Cushman & McCulloch, 

 1948) Figs 1.9,25-27 



1899 Haplophragmium nanum Brady; Millett: 360; pi. 5, 

 figs 9a-c {non Brady, 1881). 



1939 Trochammina pacifica Cushman var. simplex Cush- 

 man & McCulloch: 104; pi. 11, fig. 4 (non Friedburg, 

 1902). 



1948 Trochammina pacifica Cushman var. simplissima 

 Cushman & McCulloch: 76 (nomen novum). 



1956 Trochammina simplissima Cushman & McCulloch; 

 Bandy: 198; pi. 29, figs 14a-c. 



1979 Paratrochammina simplissima (Cushman & McCul- 

 loch); Bronnimann: 10; figs 2,3,6A-J,8A-H (q.v. for 

 full synonymy). 



Remarks. Millett's illustrated specimen, attributed to H. 

 nanum Brady (op.cit. pi. 5, figs 9a-c; reproduced here as Figs 

 1.9a-c), is a sinistrally coiled specimen with 5 chambers in the 

 final whorl. From the drawings it can be seen that the 

 chambers of the final whorl are strongly compressed in an 

 axial direction and the ultimate chamber is radially elongate. 

 The intercameral sutures are well defined and the agglutinant 

 of the spiral side appears to be distinctly coarser than that of 

 the umbilical side. The aperture, which is an essential generic 

 criterion, is only visible in edge view and its umbilical 

 extension, if any, cannot be seen in the drawing of the 

 umbilical side. We have searched the Millett Collection to 

 find this figured specimen but the closest to it is a dextrally 

 coiled individual (Figs 25-27), so it is possible that Millett's 

 drawings could be reversed. Our figured specimen is 

 undoubtedly Paratrochammina simplissima (Cushman & 

 McCulloch). The single umbilical aperture is an elongate 

 interiomarginal slit in the final septum, which extends from 

 the surface of the first chamber of the final whorl onto that of 

 the penultimate chamber. Its length is about 120 yun and it is 

 lined by a weakly uplifted border of agglutinated fragments. 

 The final whorl has 5 chambers, as in the original drawing, 

 but the ultimate chamber, perhaps, is radially not as elongate 

 as in Millett's figure. The test consists of 10 chambers, the 

 coiling is rather tight and the axial depression (umbilicus) is 

 therefore virtually closed. The radial sutures are well defined 

 on both sides and the outline of the test is weakly lobate; the 

 periphery, as seen in edge view, being compressed but still 

 rounded. The spiral side is almost flat and the umbilical side 

 slightly concave. As in Millett's illustrated specimen, ours is 

 also more coarsely agglutinated on the spiral side than 

 umbilically. 

 The marine, shallow water P. simplissima differs in all 



