260 THE FOEAMINIFEEA 



the species appear to be of Permian age. Quite 

 recently Spandel has, however, considerably added 

 to the Zechstein foraminiferal fauna, and cites the 

 following additional genera : Hyjjerammina, Cornu- 

 spira, Linguliiia, Frondicularid, Vag inulina ,Marginu- 

 lina^ GeinitzeUa (afterwards changed to Geinitzina), 

 and Lnnucammina} 



By the presence of forms like LinguJina, Fron- 

 diculaiia, and Vaginnlina we are reminded of the 

 prevalent characteristics of the Mesozoic foramini- 

 feral faunas, in which the above-named genera are 

 conspicuous in increasing abundance as we ascend 

 the geological scale. The prototypes of these hyaline 

 forms may have been the somewhat irregular and 

 subarenaceous isomorphs found in the Carboniferous 

 System w^hich have been described by Brady under 

 the generic names of Stacheia And Nodosinena. 



The Triassic System as a rule is not prolific 

 in Foraminifera. The Muschelkalk has yielded 

 organisms in some abundance belonging presumably 

 to the genera Glohigerlna and Orhulina. Giimbel 

 has described a fauna from the oldest strata of the 

 Bunter Sandstone in the Alps, which is remarkable 

 from the fact that it includes two species of Eitdu- 

 thyra, a genus which otherwise is unknown outside 

 the Carboniferous System. Associated with Endo- 

 thyra are the following genera, Ammodiscus, Valcu- 

 lina, Bulimma^ and Lingulina. Several genera, 



^ Lunucammina is a inodificiition of Geinitzina in which the vertical 

 axial depression exists only on one side, the other side forming, so to 

 speak, a rounded dorsal surface. 



