FORAMI]^irEEA OF THE KEEIMBA AECHIPELAGO. 585 



6 Stations. 



Less widely distributed than the closely allied S. ovata, but occurring in company 

 with that species at many Stns. There are numerous transition-forms characterized 

 by an intermediate number of chambers, viz., six. Sidebottom states that his 

 species S. ovata has occasionally six visible chambers. When, as is usually the case, 

 these six-chambered specimens have a compressed sectional outline, it becomes 

 doubtful whether they should be assigned to one or the other species, and even 

 whether S. ovata is not merely a variety of Schlumberger's earlier species. 



Subfamily Hauerinin^. 

 ArticuliiNA d'Orbigny. 



93. Articulina sulcata Eeuss. 



Articulina sulcata Eeuss, 1849-50, FOT. p. 383, pi. iv. (xlix.) figs. 13-17. 

 „ Brady, 1884, FC. p. 183, pi. xii. figs. 12, 13. 

 „ Brady, Parker, & Jones, 1888, AB. p. 215, pi. xl. fig. 11. 

 „ „ Egger, 1893, FG. p. 243, pi. iii. fig. 5. 



„ Millett, 1898, etc., FM. 1898, p. 510. 

 „ Sidebottom, 1904, etc, RFD. 1904, p. 16, pi. iv. figs. 16, 17; text-fig. 5. 



11 Stations. 



Occurrence rare to frequent, but never abundant. At Stns. 1 and ? B the species 

 attains its maximum development of frequency and size. 



It seems not improbable that Reuss's species may represent merely an arrested or 

 young form of A. sagra, as the few specimens of A. sagra found at Kerimba are of a 

 diminutive type as compared with the normal development of the species, and in their 

 initial milioline portion agree in size with the specimens of A. sulcata occurring in the 

 same dredging. 



94. Articulina sagra d'Orbigny. (PL XLV. figs. 22-25.) 



Articulina sagra d'Orbigny, 1839, FC. p. 183, pi. ix. figs. 23-26. 

 Vertehralina mucronata d'Orbigny, 1846, FFV. p. 120, pi. xxi. fig.s. 18, 19. 

 Articulina sagra Brady, 1884, FC. p. 184, pi. xii. figs. 22-24. 

 „ Millett, 1898, etc., FM. 1898, p. 511. 

 „ „ Sidebottom, 1904, etc., EFD. 1904, p. 17, pi. iv. figs. 18-20; text-fig. 6. 



6 Stations. 



A few small individuals only, and at Stn. 5 a broken terminal chamber which, from 

 its very large size, can hardly have belonged to A. sulcata. At Stn. ■? B a number of 

 individuals were found which seem to represent a transition-stage between A. sulcata 

 and A. sagra, the terminal chamber being added to a normal A. sulcata shell, but 

 being formed in the normal A. sagra manner, except that it is much more produced 



4o 2 , 



