Heron-Ai.i.kn and Earland — study of Vcrneuilina folyniropha. 169 



mineral acids) docs uoL arise from a mixing into Lhc shell of sand-grains 

 cemented together appears to be probable from the smooth upper surface of 

 the sliell, and the histcilogical facts revealed liy fragments." 



He records that his F. silicea is not the only Foraminifer " with a 

 siliceous cuirass," as he has had under Ins observation a living arenaceous 

 polythalamian (which he describes, but does not figure or name), and calls 

 attention to ilie two d'Orbignyan species, Spirolina {llaplophraf/mium) 

 agglutinans and Bigcnerina af/i/lutmcms "" {B. nodosaria, d'Orb.). 



In 1858 Williamson described the form as Bidimina scabra,^" calling 

 attention to Schultze's species {ante), and noting the difference in the aperture 

 as described. He properly doubts the accuracy of Schidtze's figure in this 

 respect, and regards the two as identical, which they are. 



It was Carpenter, Parker, and Jones, in 1862, who recognized H. arcnacca 

 (scaira) Will, as an arenaceous Textularian,*'' transferred it to the genus 

 Verueuilina of d'Orbigny, and suggested in the Appendix (p. 311) the name 

 Vcrne^dlina polystropha. The genus Verueuilina was created by d'Orbigny, 

 and was subsequently diagnosed as follows by Parker and Jones in 1 865 " 

 in describing this species : — 



'J'extularia agglutinans, d'Orb., var. ( Vcrneuilina) polystropha, Eeuss., sp. 



" When Textulariae have a triple row of alternating chambeis, as is not 

 unusual with them, they are termed Verneuilinae ; having commenced 

 triserially, they may afterwards take on a biserial or uniserial arrangement 

 of chambers, and are known as Gaudryina, Clavulina, &c. Some that have a 

 triple series of chambers are so much twisted on the axis as to liave a 

 buliminoid aspect ; a slight approach to tins condition is shown in 

 VerneuiUna polystropha (refs. as above). In Verneuilina the aperture ceases 

 to be transverse, becoming drawn upwards, as it were, across the septal plane 

 more and more in the later chambers, until it ceases to be even a notch, and 

 becomes terminal and round, as it is in Bigeuerinae. 



" F. polystropha may be said to be a small, vesicular, arrested verneuiline 

 Textularia ; sandy, twisted on its axis, and very red in colour. It is of wide 

 distribution, living in all latitudes ; it is found fossil in the Tertiary and 

 Cretaceous beds." 



*" A. d'Orbigny : Forarainiferes fossiles du Bassin Tertiaiie de Vienue. Paris, 1S46. 

 p. 137, PI. vii, tigs. 10-12, and p. 238, PI. xiv, figs. 8-10. 



™ W. C. Williamson : " Recent Foiaminifera of Great Britain " (Ray Society), 1868, 

 p. 65, figs. 136, 137. In the explanation of the plates it is called B. areiuicea. 



*' Loc. cit, note 15, p. 192. 



s- W. K. Parker and T. R. Jones : " iS'orth Atlantic .uid Arctic Foraiiiiiiifci.i," Phil. 

 Trans. Roy. Soc, 18G5, p. 371, PI. xv, fig. 20. 



K.l.A. PJSOC, vol., XXXV. SKCI. IS. [ C* J 



