540 Transactions of the Society. 



to extend the subgenus Bifarina of Parker and Jones, so that it may 

 include all the members of the series, and thus avoid the disadvantage 

 of instituting a new name for forms which admittedly are scarcely 

 separable. 



In the genus Pleurostomella the triangular chambers with zigzag 

 sutures are of common occurrence. Other figured forms of similar 

 construction are Textularia laminar is Costa * and Bolivina cylin- 

 dracea Schwager.j The single specimen from the North Atlantic, 

 south-east of George's Bank, figured by Flint + as Bolivina porrecta 

 Brady, possesses the three different forms of chambers as in Bifarina 

 elongata. It comes from a depth of 956 fathoms, and is much larger 

 than the Malay examples, having a length of 1 mm. 



Bifarina elongata is very common in the Malay Archipelago, and 

 occurs at most of the Stations in both Areas. 



Bifarina porrecta Brady sp., plate IV. fig. 3. 



Bolivina porrecta Brady, 1881, Quart. Journ. Micr. Sci., vol. xxi, 

 n.s. p. 57. B. porrecta Brady, 1884, Chall. Kept., p. 418, pi. lii. fig. 

 22. B. porrecta (Brady) Egger, 1893, Abhandl. k. bayer. Akad. 

 Wiss., CI. II. vol. xviii. p. 300, pi. viii. figs. 7-9, 46, 47. 



This is one of the commonest forms of the region, and occurs in 

 abundance at nearly all the Stations. The walls are thin and clear, 

 as stated by Brady of the ' Challenger ' examples, but differ from them 

 in being coarsely perforated. The aboral portion of the test is usually 

 of a tawny colour, which becomes fainter and disappears when it 

 reaches the triangular segments. In the specimens figured by Egger 

 the change of form in the later chambers is not apparent. 



Obtained at three 'Challenger' localities, namely: — Off Culebra 

 Lland, West Indies, 390 fathoms ; off Tahiti, 420 fathoms ; and in 

 Humboldt Bay, north coast of Papua, 37 fathoms. 



The ' Gazelle ' Stations are Mauritius, 411 metres and 347 metres ; 

 and a rather doubtful locality, apparently on the western coast of 

 New Guinea, " Galewostrasse " St. 104 a. 3 metres. 



Bolivina d'Orbigny. 



Bolivina. punctata d'Orbigny. 



Bolivina punctata d'Orbigny, 1843, Foram. Amer. Merid., p. 63, 

 pi. viii. figs. 6-12. B. punctata (d'Orb.) Woodward and Thomas, 

 1885, 13th Ann. Kept. Geol. and Nat. Hist. Survey of Minnesota 

 for 1884, p. 109, pi. iii. fig. 12. B. punctata (d'Orb.) Sherborn and 

 Chapman, 1886, Journ. R. Micr. Soc, vol. vi. p. 743, pi. xiv. fig. 10. 

 B. punctata (d'Orb.) Malagoli, 1888, Boll. Soc. Geol. Ital., vol. vii. 

 p. 375, pi. xiv. figs. 1-4. B. punctata (d'Orb.) Terrigi, 1891, Mem. 



* Atti Accad. Pontaniana, vol. vii. fasc. 2, 1856, p. 290, pi. xxiii. fig. 15. 

 t Boll. E. Com. Geol. d'ltalia, vol. ix. 1878, p. 528, pi. i. fig. 18. 

 X Kept. U.S. Nat. Mus. for 1897 (1899), p. 292, pi. xxxviii. fig. 2. 





