Figure 31: Chomata.
A-C: Eowedekindellina sp. Permian, Iran, collection, oblique, subaxial and subequatorial sections, transmitted light micrographs, and model. Note poleward extension of chomata forming a basal layer. D-F: ordinary chomata in Triticites sp., equatorial and axial sections, transmitted light micrographs and model. Lower Permian, Spitzbergen. Note in D the sector-wise appearance and disappearance of the chomata due to the slight obliquity of the section.
ath: antetheca; c: choma; c*: cutoff choma stressing the uncertainty about the connection between the choma and the antetheca; fl: fluted septa; kth: keriotheca; s: septum; sp: septal pores; spth: spirotheca; t: tunnel.