Palynological study of three different taxa, viz., Eria dalzellii Lindl., Rhynochostylist retusa (L) BI. and Oberonia brunoniana Wight using SEM has been made. All these three taxa have monoaperturate
condition with ring-like annulus along with uneven disrupted projections. They also exhibit variation in density of excrescence. Dense rugulate excrescence is noted in R. retusa (L) Blume and sparse
rugulae in E. dalzellii Lindl. But intermediate type of density of rugulate excrescence is observed in
O. brunoniana Wight.