Growth and Physiology of Foraminifera in the Laboratory; Part 4 — Monoxenic Culture of an Allogromiid with Notes on its Morphology

SYNOPSIS. A polymorphic allogromiid (our strain NF) was isolated in monoxenic culture but attempts at its axenic culture failed. Growth of monoxenic cultures was stimulated by various metals and vitamins. The morphology and life cycle of this allogromiid with a prominent collar have been studied in detail. It varied in form from ovoid to elongate bioral “Shepheardella‐like” forms and to irregular polyoral organisms. The organisms ranged in length from 56–385 μ (118 μ± 50.54) and in width from 35–385 μ (99 μ± 39.34). The number of nuclei per organism averaged 8.9 ± 6.3 (range 1–40). Reproduction of “Shepheardella‐like” forms was by binary fission. Three types of budding have been observed and, rarely, schizogony. No evidence for sexual reproduction has thus far been seen.