FOEAMINIFEEl OF THE KERIMBA AEClilPELAGO. 561 



three species, as might be expected, becomes highly involved when the figures of 

 different authors are compared with the original type. Schlumberger's figures of 

 M, suborbicularis are typical M. wehbiana. Millett's M. suhorhicularis is M. webbiana 

 as regards the coarseness of its striation, while nearer d'Orbigny's type in the 

 embracing character of the chambers. 



All three types occur at Kerimba, but M. webbiana is by far the most abundant, as 

 in our experience it is elsewhere. This species is generally distributed, but the 

 number of specimens at any particular Stn. is never large ; it is best and most 

 abundant at Stn. 11. M. Jichteliana is extremely limited, but is the sole representative 

 of the group at Stns. ■? B and 13, and is well developed and moderately abundant at 

 Stn. \ X, where the other forms are rare and poor. M. suborbicularis is extremely 

 rare, but typical specimens were found at a few Stns. 



With regard to the reference to Schlumberger, 1893, MGM., su])ra, the author, in 

 referring his specimens to Quinqueloculina suborbicularis, on account of their presenting 

 five visible chambers instead of the three represented in d'Orbigny's type, Triloculina 

 suborbicularis, appears to have overlooked the fact that d'Orbigny had already utilized 

 this specific name for an entirely different quinqueloculine miliolid Quviquelocidina 

 suborbicularis (TMC. p. 302, no. 29), which is a smooth-shelled form, apparently in no 

 way related to the triloculine striate form. An inspection of the types both at 

 La Rochelle and in Paris entirely bears this out. 



(Group of 31. trigonula.) 



35. Miliolina trigonula (Lamarck). 



Miliulites trigonula Lamarck, 1804, etc., AM. 1804, vol. v. p. 351. no. 3. 



„ „ Lamarck, 1816, etc., ASV. vol. vii. p. 612 ; 1835, etc. vol. .\i. p. 290. no. 3. 



Triloculina trigonula d'Orbigny, 1826, TMC. p. 299. no. 1, pi. xvi. figs. 5-9, Modele no. 93. 

 Miliolina trigonula Wilhamson, 1858, RFGB, p. 84, pi. vii. figs. 180-182. 



Brady, 1884, FC. p. 164, pi. iii. figs. 14-16. 



Goes, 1894, ASF. p. 115, pi. xxii. fig. 870. 



17 Stations. 



Universally distributed, and at most Stns. showing considerable variation, the 

 species running imperceptibly into M. tricarinata. The difficulty of separating the 

 two forms is greatest at those Stns. [e. g., 5, 6, 7, 10, and 12) where the species 

 reaches its maximum development in size, the young specimens in both species being, 

 as a rule, more typical than the larger ones. At Stns. 2, 3, and 13 the species 

 exhibits a dehiscent tendency, very marked in occasional specimens, in which the 

 final chambers are separated by deep grooves from the earlier ones, suggesting the 

 Triloculina plicata of Terquem (T. 1878, FIE. p. 61, pi. vi. (xi.) fig. 2). At Stns. 1, 

 8, and 9 specimens irregularly sulcate in the neighbourhood of the aboral extremity 

 of the final chamber occurred. At Stn. 13, where the species was very variable, 



4l2 



