FOEAMINIFEEA OF THE WEST OF SCOTLAND. 239 



137. Bolivina difformis (Williamson). 



Textularia variabilis, var. difformis, Williamson, 1858, RFGB. p. 77, pi. vi. figs. 166, 167. 

 Bolivina difformis, Brady, 1887, SBRF. p. 899. 



„ „ Heron-Allen & Eailaud, 1913, CI. p. 65. 



14 Stations. 



Fairly generally distributed, but not generally abundant, tbe best individuals at 

 Stns. 3, 10, and 19. There is very little differentiation, but the specimens generally 

 represent one or other of two types : (i.) a thin flat form closely allied to B. d'datata, and 

 (ii.) a stouter form with limbate sutures often tending to obscurity of the surface. 



138. Eolivina gramen (d'Orbigny). 



Vulvulina gramen, d'Orbigny, 1839, FC. p. 148, pi i. figs. 30, 31. 

 Bolivina gramen, Heron-Allen & Earland, 1913, CI. p. 69, pi. v. figs. 4, 5. 



5 Stations. 



Very rare, only an occasional specimen being found, except at Stn. 4, where it is 

 fairly frequent and typical. This species has been recorded from Britain by ourselves 

 (ut supra), and this appears to be the only record since it was first described by 

 d'Orbigny (ut supra) from Cuba. 



139. Bolivina beyrichi, Reuss. (Plate 41. fig. 15.) (New to Britain.) 



Bolivina beyrichi, Eeuss, 1851, FSUB. p. 83, pi. vi. fig. 51. 

 Brady, 1884, FC. p. 422, pi. liii. fig. 1. 



2 Stations. 



Several fine and typical specimens at Stn. 4, characterized by the marginal processes 

 and bands of clear shell-substance at the base of each chamber which mark this species. 

 As a recent form, this is tbe first British record, but Wright records it from Post -tertiary 

 deposits at Derry and Shellag (J. Isle of Man Nat. Hist. Soc. 1902, vol. hi. p. 628; and 

 Proc. Belfast Nat. Field C. 1900-1, p. 604). The species is widely distributed all over 

 the world, but, as a recent species, has not been recorded farther north than the coast 

 of Portugal. 



140. Eolivina asnariensis (Costa). 



Brizalina amariensis, Costa, 1853, etc., ERN. 1856, p. 297, pi. xv. figs. 1, 2. 

 Bolivina <enariensis, Brady, 1884, FC. p. 423, pi. liii. figs. 10, 11. 



12 Stations. 



Generally distributed, but not very abundant except at Stns. 2, 18, and 20. None 

 of the individuals exhibit the parallel longitudinal costae which mark tbe typical 

 J3. amariensis. These costate specimens, however, appear generally to be confined to 

 deeper water than any of these dredgings. The specimens run gradually into B. d'datata, 

 Reuss. At several Stns. there is a tendency to form either a marginal keel or serrate 

 processes at tbe extremities of the chambers; this is especially noticeable at Stn. 2. At 

 this Stn., and also at Stn. 4, many individuals twisted along the long axis occur. 



37* 



