FORAMINIFERA OF THE NORTH PACIFIC OCEAN. 77 



BILOCULINA VESPERTILIO Schlumberger. 

 Plate 30, fig. 1. 



Biloculina ringens H. B. Brady (not Lamarck), Rep. Voy. CJiallenger, Zoology, 



vol. 9, 1884, p. 142, pi. 2, fig. 8. 

 Biloculina vespertilio Schlumberger, Mem. Soc. Zool. France, vol. 4, 1891, 



p. 174, pi. 10, figs. 74-76, text figs. 20-22. 



Description. — Test in front view subcircular, the apertnral end 

 broadly truncate, in end view very tumid; the periphery rounded, 



Fig. 37.— Biloculina vespertilio Schlumberger. X5. Outline figure of very large specimen 



from ''Albatross" D5056 in Suruga Gulf, Japan. 

 Fig. 3S.— Biloculina vespertilio Schlumberger. X50. Apertural portion of test in smaller 



specimen with the more typical sinous form of aperture and too^h with large lateral wings. 



From D5056. 



wall smooth except for small transverse ridges on the adult chambers ; 

 suture slightly indentate along the edges; aperture elongate, with a 

 large tooth, the center with a slight point, the ends broadly rounded, 

 the apertural opening narrow, curving about it. 

 Diameter, nearly 2 mm. 



Fig. 39.— Biloculina vespertilio Schlumberger. X50. Apertural portion of test in very large 

 specimen where aperture has become straighter and the tooth less conspicuous. From 

 D5056. 



Distribution. — Specimens which were very similar to those de- 

 scribed and figured by Schlumberger and by Brady were found in 

 some numbers at Albatross station D5056 in 258 fathoms off the coast 

 of Japan. 



The apertural characters are very striking, having a rather beautiful 

 series of curves. 



