FORAMINIFERA OP NORTH PACIFIC OCEAN. 



71 



Although Brady referred the recent species to the cretaceous G. 

 filiformis, it seems from a comparison of the material obtained with 

 the original description and figure, that the two species are not the 

 same, and the recent species is therefore differentiated under another 

 name. It is smooth and has the aperture somewhat in from the 

 edge, surrounded by a raised ridge. 



TRITAXILINA, new genus. 



Clavulina (part) H. B. Brady, Quart. Journ. Micr. Sci., vol. 21, 1881, p. 54. 



Tritaxia (part) H. B. Brady, Rep. Voy. Challenger, Zoology, vol. 9, 1884, p. 390. 



Description. — Test in the early portion triserial, later becoming 

 biserial or uniserial; wall arenaceous; aperture in the adult, central 

 and terminal, in the young like Tcxtularia or Verneuilina, in adult 

 condition with peripheral teeth projecting into the apertural opening; 

 interior labyrinthic. 



This genus includes a single species, T. caperata (H. B. Brady), 

 which differs from the species of Tritaxia in the form of the test, the 

 aperture, and the labyrinthic interior of the test. 



TRITAXILINA CAPERATA (H. B. Brady). 



Clavulina caperata H. B. Brady, Quart. Journ. Micr. Sci., vol. 21, 1881, p. 54. 

 Tritaxia capcmta H. B. Brady, Rep. Voy. Challenger, Zoology, vol. 9, 1884, p. 

 390, pi. 49, figs. 1-7. 



Description. — Test fusiform, the early portion triserial, roughly 

 triangular in cross section but with well rounded angles, the later 

 portion becoming biserial 

 or uniserial and circular in 

 cross section; apical end 

 rat her acut ely p o i n t e d ; 

 apertural end truncate or 

 broadly rounded, chambers 

 numerous ; wall thick, com- 

 posed of fine arenaceous 

 material, in part traversed 

 by long pore canals leading 

 from the chamber to the 

 exterior; interior of test 

 labyrinthic; outer part of 

 wall with a wrinkled appear- figs. 112-114— tritaxtlinacapebata. x 16. ii2,a,APER- 



„„„„ J„~ +^ + 1. 4-W. 1 „• „. TURAL VIEW. 1 14, SPECIMEN CUT LONGITUDINALLY, SHOW- 



ance due to the thickening mG LABYRINTHIC INTEEIOR (AFTER Brady) . 

 of the chamber wall just 



above the sutures; sutures distinct; aperture in the young like 

 Verneuilina, in the adult becoming terminal and central with a 

 peripheral border of inwardly projecting teeth; color gray. 

 Length up to 2.5 mm. 



