- GeoRef, Copyright 2004, American Geological Institute. Reference includes data from Bibliography and Index of Geology Exclusive of North America, Geological Society of America, Boulder, CO, United States
New forms of hystrichospheres from upper Jurassic strata in the vicinity of Weymouth, Dorsetshire, southern England, are classified and described as Hystrichosphaeridium cribrotubiferum n.sp., Baltisphaeridium downiei n.sp., B. lumectum n.sp., Polystephanosphaera valensii n.g. n.sp., and P. paracalathus n.g. n.sp.