66 BULLETIN 11, UNITED STATES NATIONAL MUSEUM. 



PULVINULINA GILBERTI Bagg. 



Pulvinulina gilberti Bagg, Proc. U. S. Nat. Mus., vol. 34, 1908, p. 161, pi. 5, 

 figs. 11-15. 



Description. — "The test is highly vaulted upon the interior side, 

 with deeply sunken septa, which extend from the margin to the 

 umbilicus in an almost straight line, as in Pulvinulina canariensis 

 d'Orbigny, which this species somewhat resembles. The segments 

 are, however, more compactly built, and the aperture, a neatly 

 shaped arch, lies midway between the periphery and the umbilicus 

 upon the inferior surface. The superior surface instead of being 

 vaulted as in P. canariensis, is almost complanate and the periphery 

 is almost keeled, being quite sharp and distinct, although somewhat 

 lobulated on the last two chambers of the ultimate whorl. There are 

 five segments visible in the last convolution, and they are equally 

 distinct upon both surfaces. 



"The shell is very minute and firmly built. It has a slight resem- 

 blance to Truncatulina dutemplei (d'Orbigny), but the margin is sharp 

 and more angular in the present form, and the septal lines upon the 

 inferior surface are much more depressed and the chambers more 

 inflated. It is somewhat doubtful whether the present form should 

 be considered a distinct species or only a variety of Pulvinulina 

 menardii, which it resembles. It is much smaller than P. menardii, 

 much more vaulted upon the inferior surface, and a little more 

 closely involute. The septal depressions also are strong, deeply 

 sunken on the lower side and extend straight to the center. Upon 

 the superior side they are strongly curved as in P. menardii. There 

 are five of these chambers in the final convolution. The ultimate 

 chamber is largest, and in its outline reminds one of the auriculate 

 type of Pulvinulinae, but it is not so extended from the whorl. It is 

 not a young form of P. menardii.^ 



Distribution. — "Present and rather common at [Albatross] station 

 H4555," in 1,398 fathoms, off the Hawaiian Islands. 



In the figures, which are not very distinct, this species seems to 

 me to very greatly resemble P. menardii. An examination of the 

 specimens also seems to confirm this. Just what disposal should be 

 made of the form there is not sufficiently well marked material to 

 decide. The descriptive notes aie from Bagg. 



Genus ROTALIA Lamarck, 1804. 



Nautilus Linnaeus (part) Syst. Nat., ed. 12, 1767, p. 1162. 



Rotalia Lamarck, (type, Nautilus beccarii Linnaeus), Ann. Mus., vol. 5, 1804, 



p. 184.— d'Orbigny, Ann. Sci. Nat., vol. 7, 1826, p. 275.— H. B. Brady, 



Rep. Voy. Challenger, Zoology, vol. 9, 1884, p. 702. 



Description. — Test free, composed of numerous chambers arranged 

 in a flattened spire, the two sides biconvex or varying from flat above 



