52 



BULLETIN 104, UNITED STATES NATIONAL MUSEUM. 



The genus PiluUna based upon P. jefreysii by Carpenter is rather 

 rare, known hitherto from but two species, the type from the North 

 Atlantic and a second species, P. ovata, which I described from the 

 North Pacific. Where the species occur they are often in great num- 

 bers but the known areas of distribution are very limited. 



PILULINA JEFFREYSII W. B. Carpenter. 



rUuUiia, specie.s, W. B. Oarpexter, Descr. Catal. Obj. Deep-Sea Dredging 

 1870, p. 5. 



PiluUna jejfreysii W. B. Carpenter, The Microscope, ed. 5, 1875, p. 532, figs. 

 d, e,; ed. 6, 1881, p. 560, figs. 319rf, e.—H. B. Brady, Rep. Voy. Challenger, 

 Zoology, vol. 9, 1884, p. 244, pi. 25, figs. 1-6.— Flint, Rep. U. S. Nat. Mus., 

 ]897 (1899), p. 266, pi. 5.— Rhumbler, Arch. Prot., vol. 3, 1903, p, 249, 

 fig. 88. 



Description. — Test free, subspherical, or occasionally oval; com- 

 posed of a single chamber, undivided ; wall comparatively thin, made 

 up of long sponge spicules felted together, the interstices filled with 

 broken spicules and a white amorphous material, probably siliceous; 

 smooth both inside and outside; the spicules on the outside more or 

 less longitudinally arranged; aperture an elongate slit, straight or 

 more often doubly curved and S-shaped, with shghtly raised lip. 



Diameter, up to 3.5 mm. 



Bistrihution. — Brady's specimens of this species were from three 

 stations of the Porcupine dredgings south of the Rockall Bank, 

 depths 1,476, 630, and 1,215 fathoms. Flint records the species 

 from the North Atlantic without station. Apparently this is the 

 extent of our recorded knowledge of this species. In the Albatross 

 material I liave examined it has occurred at the following stations: 

 D2036 in 1,735 fathoms, bottom temperature 38° F.; D2096 in 1,451 

 fathoms, bottom temperature 37.5° F.; D2221 in 1,525 fathoms, bot- 

 tom temperature 36.9° F.; and 1)2229 in 1,423 fathoms, bottom 

 temperature 37.7° F. These stations are southward of Georges 

 Banks. At the latter stations specimens were very abundant, sev- 

 eral vials full being obtained from tlie material. 



There apparently is little or no calcareous material used in the 

 wall of the test of this species, the test being unaffected by acids. 

 The peculiarity of its distribution is remarkable, for material was 

 examined from numerous stations in this same region. 



