. Bulletin - United States National Museum. Science. Glintzboeckel and Magn6 (1955, p. 154) have shown that Globigerinelloides algeriana occurs about 200 meters below an Aptian (Upper Gargasian) ammonite assem- blage and it is regarded by them as a "good guide fossil for the Aptian of North ; Figured paratype (Cushman Coll. 56790) from green- ish blue marls of Aptian age, Djebel Menaouer, between Relizane and Uzes-le-Duc, western Algeria. Collected by A. ten Dam. Range: Aptian. STUDIES IN FORAMINIFERA 23 Genus Planomalina Loeblich and Tappan, 1946 ' Plate 1, Figures 2a-3b Plan
. Bulletin - United States National Museum. Science. Glintzboeckel and Magn6 (1955, p. 154) have shown that Globigerinelloides algeriana occurs about 200 meters below an Aptian (Upper Gargasian) ammonite assem- blage and it is regarded by them as a "good guide fossil for the Aptian of North ; Figured paratype (Cushman Coll. 56790) from green- ish blue marls of Aptian age, Djebel Menaouer, between Relizane and Uzes-le-Duc, western Algeria. Collected by A. ten Dam. Range: Aptian. STUDIES IN FORAMINIFERA 23 Genus Planomalina Loeblich and Tappan, 1946 ' Plate 1, Figures 2a-3b Planomalina Loeblich and Tappan, 1946, Journ Paleontol vol. 20, No. 3, p. 257, 1946. Type species: Planomalina apsidostroba Loeblich and Tappan, 1946. Fixed by origmal designation and monotypy. Test free, planispiral, biimibilicate, involute to par- tially evolute, lobulate in outline; chambers spherical to ovate to angular rhomboid; sutures radial, straight or curved, elevated or depressed; wall calcareous,finely perforate, radial in structure, surface smooth or orna- mented with nodes and keel; aperture interiomarginal, an equatorial arch, with lateral extensions reaching back at either side to the septum at the base of the chamber, the lateral umbUical portions of successive apertures remaining open as supplementary relict aper- tures after the equatorial portion is covered by the succeeding chambers, these small rehct slits and promi- nent bordering lips giving a characteristic appearance to the umbilical region. Remarks: Originally believed to be related to Anom- alina because of the relatively coarsely perforate, planispiral test, Planomalina is now shown to possess lateral relict apertures in addition to the primary interiomarginal equatorial apertm-e, which with the planispiral plan of growth suggests a relationship to such planktonic genera as Hastigerinoides. Another excellently preserved species here described, which lacks the surface ornamentation of the type species, s
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