FORAMINTFERA OF NORTH PACIFIC OCEAN. 5 



SPIROPLECTA BULBOSA, new species. 



Description. — Test compressed, the early portion nearly circular, the 

 later portion elongate, narrower, rectilinear; the chambers numerous, 

 those of the early portion coiled, involute, the later biserial; wall cal- 

 careous, perforate, smooth; color white. 



Length about 0.40 mm. 



Type-specimen.— -Cat. No. 832S, U.S. 

 N.M., from Albatross station D4957 in 

 437 fathoms off the coast of Japan. 



This species is small, and has a remark- 

 ably large portion of the 

 test made up by the spi- 

 rally coiled chambers. Fig. 

 1, 6, shows the arrange- 

 ment of the chambers in 

 the megalospheric form, 

 making a complete volu- 

 tion about the proloculum. 



Subfamily 3. TEXTU- 



Test typically biserial, 

 wholly orin part,the early 

 portion in the micro- 

 spheric form Often with a FlG " i-*™ ™™ b ulbosa. a, view from exterior, 



1 SHOWING LARGE PROPORTION OF THE CIRCULAR PART OF THE 



few COned chambers, fol- test. X 120. 6, optical section of the test, showing 

 lowed bv the biserill THE C0MPLETE volution made by the coiled chambers 

 . ^ about the proloculum. x 200. 



chambers; later cham- 

 bers variously modified in the different genera, uniserial, broadly ex- 

 tended, etc. ; wall either arenaceous or calcareous and hyaline, perforate ; 

 aperture single, or in a few cases, many present in a single chamber. 

 Tins subfamily includes those forms which are essentially biserial 

 in their development, not having reached the triserial stage anywhere 

 in their stages of development. The stages in the simpler genera are 

 like those of Spiroplecta, except in duration, the biserial condition 

 being taken on much earlier than in that genus. Variously modified 

 forms occur as in the uniserial arrangement in Bigenerina, the 

 broadly flaring later growth of Pavonina, and the peculiarly modified 

 aperture in Pleurostomella. 



Genus TEXTULARIA DeFranee, 1824. 



Textularia DeFrance (type, T. sagittula DeFranee) Diet, des Sci. Nat., vol. 32, 

 1824, p. 177; vol. 53, 1828, p. 344; Atlas Conch., pi. 13, fig. 5. 



Textilaria Ehrenberg, Abh. d. k. preuss. Akad. Wiss., Berlin, 1839, p. 135. 



Gravimostomum Ehrenberg (part), Abh. d. k. preuss. Akad. Wiss., Berlin, 1839, 

 p. 129. 



Plecanium Reuss, Sitz. kon. Akad. Wiss., Wien, vol. 44, 1861 (1862), p. 383. 



Description. — Test elongate, tapering, composed of two series of 

 alternating chambers ; wall calcareous, in the young, hyaline and per- 



