Which is in the grass family, Pachypodium or Arrhenatherum?
Arrhenatherum Arrhenatherum, commonly called oatgrass or button-grass, is a genus of Eurasian and North African plants in grass family.
Acrostichum Acrostichum is a fern genus in the Ceratopteridoideae subfamily of the Pteridaceae. It was one of the original pteridophyte genera delineated by Linnaeus. It was originally drawn very broadly, including all ferns that had sori apparently "acrostichoid", or distributed in a uniform mass across the back of the frond, rather than organized in discrete sori. This led Linnaeus to include such species as "Asplenium platyneuron" in the genus, because the specimen he received had sori so crowded that it appeared acrostichoid.