planispiral coiling Coiling in a single plane (see Figs. 1, 2a, b). 



planoconvex Flat on one side and bulging on the other. 



plastogamy Reproductive stage in which two specimens have 

 their umbilical surfaces cemented together (see Fig. 20). 



plug A massive deposit of shell material within or filling the 

 umbilical area. 



porcellaneous (or imperforate) wall Solid, lacking pores; hav- 

 ing a luster like porcelain. 



pore Small opening from interior to exterior of the test. 



primary aperture The major opening of the final chamber of 

 the test. 



pseudochitinous Composed of a flexible organic compound, 

 secreted by the animal, that makes up the wall or serves as 

 cement in certain species. 



pseudopodia Slender threads of protoplasm extending out- 

 ward from the living animal through the aperture (and pores 

 if any) of the test. 



quadrangular Roughly four-sided. 



quinqueloculine coiling Coiling in which five chambers consti- 

 tute a whorl; each chamber is half a coil long and the 

 chambers are added at intervals of 144° around the axis of 

 coiling (but 72° from the adjacent chamber) so that three 

 chambers are visible from one side and four from the 

 opposite side (see Fig. 7). 



radiate aperture Terminal aperture characterized by radiating 

 slits (see Figs. 2a, b, 18). 



reticulated Appearing as a meshwork or network. 



ribs Ridges of thickened shell material. 



rotaline (or trochospiral) coiling Coiling in a rising spire rather 

 than a single plane (see Figs. 3a-c). 



rugose Rough. 



sac A simple sacklike form. 



secreted Derived from the metabolic functions of the animal. 



septal bridges A series of fingerlike bridges across the 

 suture (see Fig. 23). 



septum, septa Internal wall or walls separating or subdividing 

 chambers. 



sigmoiline coiling Coiling in which each chamber is half a coil 

 long and the chambers are added at intervals of slightly more 

 than 180° around the axis of coiling, resulting in a sigmoid 

 transverse section (see Fig. 9). 



siliceous Composed of quartz grains (silica) cemented together 

 with a silica cement. 



spine, spines A needlelike projection (or projections) of shell 

 material at the initial end of the test, along the basal parts of 

 chambers, or completely covering the test. 



spiral Coiling in a ring. 



spiral (or coiled) side The side of the test on which the earlier 



whorls are visible (see Fig. 3a). 

 striae; striated Fine grooves or channels; covered with fine 



grooves or channels. 

 subglobular Approaching the shape of a sphere. 

 supplementary aperture An opening or openings other than 

 the major opening into the test; larger than pores (see Fig. 

 22). 

 supplementary chambers Smaller chambers covering or in 



addition to the larger chambers (see Fig. 21). 

 suture Line between adjacent chambers; intersection of in- 

 ternal septum and exterior wall (see Figs. 1, 2a, 3a, 4, 5, 6, 

 7a, b, 8a, b, 20, 21, 22). 

 taxa Units of any rank in taxonomy, such as genus, species, or 



subspecies (singular taxon). 

 terminal aperture At then end, rather than at the side, of the 



test (see Figs. 15, 16, 18, 19). 

 test Shell, or housing, in which the animal lives. 

 tooth A protuberance or projection within the aperture (see 

 Figs. 12, 13, 14). 



triloculine coiling Coiling in which three chambers constitute a 

 whorl; each chamber is half a coil long, and the chambers are 

 added at intervals of 120° around the axis of coiling so that 

 two chambers are visible from one side and three from the 

 opposite side (see Fig. 8). 



triserial Chambers arranged in three adjacent rows (see Fig. 6). 

 trochoid; trochospiral (or rotaline) coiling Coiling in a rising 



spire rather than a plane (see Figs. 3a-c, 20). 

 truncate As if cut off. 

 umbilical side The side of the test on which only the final 



whorl is visible (see Fig. 3b). 

 umbilicus; umbilical The central area (usually a depression) 



where the sutures that separate the chambers come together 



(see Figs. 2a, 3b). 

 uniserial Chambers arranged in a single row (see Fig. 4). 



valvelike tooth A broad plate that partly blocks the aperture 



(see Fig. 14). 

 vasiglobuline aperture Terminal aperture characterized by a 



ring of small openings (see Fig. 19). 

 wall Rigid or flexible material, porous or nonporous, that 



surrounds the living animal. 

 whorl (or coil) A ring of chambers or, in a single-chambered 



test, a complete revolution of the single chamber (see Figs. 1, 



2a, 3a, 11a, b, 21, 22). 



KEY TO SPECIES OF FORAMINIFERA 



1 Test agglutinated 2 



1 Test secreted 52 



2 (J) Test is single-chambered 3 



2 (/) Test has more than one chamber 19 



3 (2) Test is attached 4 



3 (2) Test is not attached 10 



5 



