FAMILY 30. HANTKENINIDAE 241 



Genus HANTKENINA Cushman, 1924 

 Plate 34, figure 18; plate 35, figures 1-3 



Genoholotype, Hantkenina alabamensis Cushman 



Hantkenina Cushman, Proc. U. S. Nat. Mus., vol. 66, Art. 30, 1924, p. 1. 

 Siderolina Hantken (not Defrance). 

 Nonionina (part) of authors. 



Test planis}3iral throughout, close coiled; chambers distinct, 

 usually nearly or completely involute, each with an acicular 

 spine at the anterior angle or becoming obsolete in the adult; 

 aperture typically arched with a basal lobe at either side. 



Upper Eocene and lowest Oligocene. 



See Cushman, A New Genus of Eocene Foraminifera (Proc. 

 U. S. Nat. Mus., vol. 66, Art. 30, 1924, pp. 1-4, pis. 1, 2). 



Genus MIMOSINA Millett, 1900 

 Plate 34, figure 19; plate 35, figure 4 



Genotype, by designation, Mimosma hystrix Millett 



Mimosina Millett, Journ. Roy. Micr. Soc, 1900, p. 547. 



Test at least in the microspheric young apparently plani- 

 spiral, later chambers biserial, chambers with a single acicular 

 spine at the outer angle; wall calcareous, vesicular, somewhat 

 spongy; aperture compound, consisting of two parts, one 

 rounded and nearly terminal, the other below near the inner 

 rim of the chamber, more elongate, arched. 



Recent. Indo-Pacific. 



Genus TRIMOSINA Cushman, 1927 

 Plate 34, figure 20; plate 35, figure 5 



Genoholotype, Mimosina spinulosa Millett, var. 



Trimosina Cushman, Contr. Cushman Lab. Foram. Res., vol. 3, 1927, 

 p. 64. 



Mimosina Millett (part). 



Test in the early stages biserial, later triserial; chambers 

 each with a single acicular spine, or these obsolete; wall cal- 

 careous, vesicular; aperture elongate, removed from the edge, 

 sometimes with a series of rounded pores in addition along the 

 basal rim of the apertural face of the chamber. 



Recent. Indo-Pacific. 



