Figure 29: Helicostegina gyralis Barker & Grimsdale 1936. Topotypes. 1 (BMNH.P.39151-2), section cut on the dorsal side of the equatorial layer showing the pillars. 2 (BMNH.P.39151-1), equatorial section. 3 (BMNH.P.39150-3), equatorial section. 4 (BMNH.P.39152-1), axial section. 5 (BMNH.P.39152), axial section. 6 (BMNH.P.39152-1), axial section. All from Eleven km SE of Sabaneta, State of Veracruz (Collection of Dr. H. Jenny, No. 1573), Mexico. Note that the lumina of the chambers do not contain subsidiary chamberlets in 5 and 6, but do in 4