26 HALKYARD, Fossil Foraminifera of the Blue Marl 



sections and breaking up several specimens that their true 

 nature could be recognized. Owing to the infiltration by calcite 

 of the specimens it has not been possible to make a section 

 from which a satisfactory drawing could be made, and this 

 infiltration has also obscured the terminal orifices. 



Found in Gatherings 5, 7, 9. Also top of Cliff 200 yds. 

 S. of l'Ermitage, Ap., 1902. 



(The species is mainly represented by fragments, but there 

 are three more or less perfect specimens from Gathering 5 

 which confirm the identification). 



Genus Placopsilina, d'Orbigny. 

 46. [Iridia diaphana, Heron- Allen & Earland,] 



[Iridia diaphana, Heron-Allen & Earland, 1914, etc., F.K.A., 

 p. 371, pi. XXXVI, and 1915, p. 607.] 



[Iridia diaphana, Heron-Allen & Earland, 1916, F.S.C., p. 37.] 



46A. Placopsilina intermedia, sp. nov. 

 PI. I, fig. 8. 



Test adherent, roughly arenaceous, consisting of three or 

 four chambers, arranged in a single curved series, each cham- 

 ber being larger than its predecessor, divisions between the 

 chambers not distinctly visible on the exterior except that 

 separating the last from the penultimate one. Orifice small, 

 situated on the longitudinal axis of the test close to the line 

 of attachment to the foreign body. Length, 1.35 mm. 



Only one specimen of this form has been met with, con- 

 sequently I am somewhat diffident in creating a new species 

 for it. At the same time the example has characteristics which 

 seem to call for a distinctive name. Its nearest ally is 

 P. cenomana, d'Orb. from which it can readily be distinguished 

 by its tapering outline, and want of the spiral commencement 

 which is so clearly marked in d'Orbigny's species. 



(We have examined Halkyard's single specimen very care- 

 fully. It has grown attached to a very thin fragment of a mol- 

 luscan shell and when examined on the underside shows at one 

 corner where the shell is broken away, a thin membraneous 

 lining free from arenaceous particles, which originally formed 

 the floor of the test. It would therefore appear to come under 

 the diagnosis of Iridia diaphana H-A. & E., assuming that this 

 basal wall was originally chitinous, which cannot of course be 

 proved in its fossil condition.) 



