88 HALKYARD, Fossil Foraminifera of the Blue Marl 



202. Frondicularia interrupta, Karrer. 



Frondicularia interrupta, Karrer, 1877, Abh. k. k. geol. Reich- 



sanst, vol. IX, p. 380, pi. XVI, b, fig. 2j. 

 F. interrupta, Brady, 1884, Chall. Rep-., p. s^3, pi. LXVI, figs. 



6-7. 



Rare, and found principally at the top of the Marl Beds. 



(Costa in 1855, (C. 1855 (1857) F.F.M.M. p. 373, pi. II. 

 fig. 25,) had already used the name Frondicularia interrupta 

 for a fossil form but, as the specimen figured by him is a 

 Vaginulina, the specific name interrupta remains available for 

 Karrer's species, a true Frondicularia.) 



203. Frondicularia arborescens, sp. nov. 

 PI. V, figs. 8-9. 



Test leaf-shaped, flat, compressed, broadest about the 

 middle, generally provided with a marginal keel. Ornamen- 

 tation on earlier segments raised, reticulated, later giving way 

 to arborescent raised lines branching from the fine limbations 

 which mark the sutures. Length, 1.45 mm. Breadth, 1.3 mm. 



This new species is very rare. It is of the complanata 

 type, and its appearance is so peculiar that it is very easily 

 recognised. Fig. 8 on pi. V represents the largest and most 

 perfect specimen found, and fig. 9 a fragment which shows 

 in a marked degree the strong reticulation of the first-formed 

 portion of the test. Only the flabelline form has been found 

 so far. 



(Halkyard's species is evidently nearly akin to Flabellina 

 reticulata Reuss (R. 1851. F.K.L. p. 30. pi. I. fig. 22.) from 

 which it differs in its greater breadth, its acute or carinate 

 margin and the comparatively irregular arrangement of the 

 reticulations between the costate edges of the chambers. 

 Decoration of any kind is a rare feature among tne Frondicu- 

 laria. A note among the Halkyard MSS. indicates that he had 

 considered the species of Reuss, but regarded it as too irregular 

 in formation and ornament to cover his specimens.) 



Genus Cristellaria, Lamarck. 

 204. Cristellaria compressa, d'Orbigny. 



Cristellaria compressa, d'Orbigny, 1846, Foram. Foss. Vienne,. 



p. 86, pi. Ill, figs. 32-33. 

 C. compressa, Brady, 1884, Chall. Rep., p. 538, pi. CXIV, figs. 



15-16. 



