198 THE FOEAMINIFEEA 



This is M typical example of the peculiar di- 

 morphous form referred to as Flahelluia. It is 

 almost essentially a Cretaceous genus, but it occurs 

 sparingly in certain Tertiary deposits, and aberrant 

 forms of Frondicularia are still found in the living- 

 condition which resemble this dimorphic type of 

 organism. The present species, F. rugosa, is well 

 known from Cretaceous strata. (Plate 10, fig. T.) 



Genus Ampliimorpliiua, Neugeboeen. 



Early chambers Frondicularian, later ones Nodo- 

 sarian. Cretaceous and Tertianj. 



Example. — .4. striata^ Reuss, ' Sitzungsb. d. k. 

 Ak. Wiss. Wien,' vol. xlvi. Abth. 1, 1862 (1863), 

 p. 57, pi. V. tig. 5. 



Reuss's example was obtained from the Upper 

 Hils Clay of Northern Germany. The only other 

 known species, A. Haueriana, Neugeboren described 

 from the Miocene of Transylvania, and Karrer has 

 recorded it from the Miocene of the Vienna Basin. 

 (Plate 10, tig. U.) 



Genus DenfaHnopsls, Reuss. 



Early chambers Rhabdogonian, later ones Nodo- 

 sarian (Dentaline). Loiver Cretaceous. 



Example. — D. suhtriquetra, Reuss, ' Sitzungsb. 

 d. k. Ak. Wiss. Wien,' vol. xlvi. Abth. 1, 1862 

 (1863), p. 57, pi. V. figs. 6 a, h. 



At the earlier part of the shell this form re- 

 sembles a triangular Dentaliiia. Reuss found his 



