128 Halkyard, Fossil Foraminifera of the Blue Marl 



varies from two, set on successive chambers of a perfect but 

 immature shell, to four set on successive chambers of a lar^e 

 but broken test, which probably had a fifth spine on its missing 

 terminal chamber. Moreover the spines, instead of being radi- 

 ally symmetrical as in the d'Orbigny-Braly types, point forward 

 from the margin, at a tangent to the spiral of growth. 



Halkyard's specimens appear to be very similar if not 

 identical with the obscure form described and figured by Hant- 

 ken (1875, Mitt. Jahr. k. ung. geol. Anst. vol. IV," pt. I, p. 79) 

 pi. XVI, fig. 1) from the "Clavulina Szaboi-Schichtcn" under 

 the name of Siderolina kochi. His description is as follows: — 

 "The shell is composed of five pouch-shaped chambers, which 

 terminate in front in a tube-shaped continuation, at the end of 

 which is placed the aperture. Both sides are nearly similar. 

 (0.5 mm)." 



Hantken's figures represent a five-chambered involute 

 spiral test. The earliest visible chamber is furnished with a stout 

 projecting spine, and the four later chambers have a blunted 

 apical projection from their forward extremity. 



Liebus in 191 1 (Liebus, Foram. mitteleocanen Mergel v. 

 Norddalmatien, Sitzb. k. Akad. Wiss. Wien. vol. CXX, pt. I, 

 (191 1), p. 78, pi. II, figs. 9-10, figures under the name of Pullenia 

 kochi (Hantken) what appears to be the same form. He very 

 properly removes it from Siderolina, and comparing its structure 

 with Globigerina digitata, Brady transfers the species to Pul- 

 lenia. Liebus writes as follows : — 



"Since the first description of this form by Hantken, (I.e., 

 p. 79, pi. XVI, fig. 1), it has never been properly treated. Hant- 

 ken himself gives no further explanation of the inner construc- 

 tion of the test. In the material examined, small fragments as 

 well as perfect examples were fairly frequent. On the surface 

 for the most part, only four arched chambers are to be distin- 

 guished, separated by deep sutures. Of these at least the 

 youngest posseses stalk-like projections, which are hollow in- 

 side. There is no clear distinction between spiral and umbilical. 

 In some instances the umbilical side is somewhat deepened. The 

 superstructure is clear, smooth and polished. It shows, roughly 

 speaking, a rotaliform plan, the chambers are in two convolu- 

 tions, almost surrounding each other. Each younger chamber 

 embraces the one in front, (i.e., each later chamber embraces its 

 predecessor. H-A & E.) so that they use this outer wall as 

 basis, and only form a new wall at the free portions. The 

 separating walls of the chambers (they are only visible in the 

 youngest portion of the test) are regularly marked with little 

 channels. 



