86 



OCEANIC TINTINNOINA OF LAST CRUISE OF CARNEGIE 



Density: Atlantic, net samples 24.65-26.67 (25.69); Pacific, 

 net sample 25.60, pump samples 24.47-25.11 (24.74). P^' 

 Atlantic, net samples 8.19-8.25 (8.21); Pacific, net sample 

 7.92, pump samples 8.00-8.19 (8.1 1). 



Xystonellopsis krammeri (Brandt) Kofoid and Campbell 



Xystoncllopsis l^i-ciinmeri, Kofoid and Campbell, 1929, p. 248, 

 fig. 485. 



The greatly elongated lorica, with herosAW^e form and 

 with spiral lines on the pedicel, has a length of 8.9 oral 

 diameters. The oral margin is sharp, with a bare suboral 

 flare. The very long bowl is subconical (7° as a whole, but 

 2° in the upper two-thirds and 10° in the aboral third). The 

 pedicel is subcylindrical and about 0.6 oral diameter in 

 length, with a scant skirt at its lower end. The lance is 

 wide conical (20°), and 0.6 oral diameter in length. 



The wall has a thickness of less than 0.07 oral diameter. 

 There are thin laminae with enclosed minute alveoles in the 

 upper bowl; in the lower bowl and pedicel these become 

 large prisms. The pedicel has 8 slightly (5°) left-turned 

 ridges which arise at the skirt and extend the whole length 

 of the pedicel. 



Length, 535 to 618^. 



Xystonellopsis \i-dmmeyi is closest to X. dahli, but is 

 much longer and has a clearer-cut skirt. It bears some re- 

 semblance to X. heros, but lacks the distinct lance, and is 

 much longer; it differs similarly from X. acuminata. 



Recorded from six stations, three each in the Atlantic and 

 the Pacific, as follows: two (28, 30) in the Atlantic equa- 

 torial region, one (34) in the Caribbean Sea, one (67) in 

 the South Pacific middle latitudes, one (145) in the North 

 Pacific middle latitudes, and one (146) in the California 

 region. 



There are 6 net samples, of which i was taken at 50 meters 

 and 5 at 100 meters. Maximum frequency, 7 per cent at 

 station 67; other records above minimum (2 per cent) from 

 stations 28, 145, 146; average in the Pacific, 3.7 per cent. 



Temperature: Atlantic, 2i?02-25?54 (23730); Pacific, 

 i6?36-2o?o7 (i8?53). Salinity: Adantic, 36.40-36.65 (36.56); 

 Pacific, 34.32-34.70 (34.44). Density: Atlantic, 24.25-25.76 

 (25.03); Pacific, 24.24-25.45 (24.72). pH: Atlantic, 8.16- 

 8.28 (8.22); Pacific, 8.09-8.34 (8.23). 



Xystonellopsis laticincta Kofoid and Campbell 



Xystonellopsis laticincta Kofoid and Campbell, 1929, p. 248, 

 fig. 469. 



The moderately long lorica, with thick suboral hand, 

 conical bowl, long pedicel, and flaring skirt, has a length of 

 6.9 oral diameters. The oral rim is thin and erect. The 

 suboral band occupies the anterior 0.21 total length. It has 

 an upper and a lower ring with diameters of 1.45 oral diam- 

 eters, and the included region is thickened. The bowl below 

 the spool is subconical (10° in the anterior 0.19 and 40° in 

 the posterior 0.13 total length). The pedicel is wide at its 

 upper end (0.55 oral diameter) and tapers (4°) to just above 

 the flaring skirt. The skirt is repeated. From its middle 



arises the lance. The lance is conical (2°), needle-like, and 

 0.56 oral diameter in length. 



The wall has a thickness of o.i oral diameter below the 

 suboral spool; in other regions it is like that of Xystonellopsis 

 abbreviata. There are left-turned striae above the skirt. 



Length, 304 to 343[-i. 



Xystonellopsis laticincta has a wider suboral band and 

 longer pedicel than X. abbreviata. It is narrower, with a 

 shorter, lower bowl, thinner pedicel, and more slender lance 

 than X. torta. The pedicel is shorter, the skirt less suddenly 

 differentiated, and the spool wider than in X. clevei. 



Recorded from two stations (86, 87) in the region of South 

 Pacific island fields, in 2 pump samples taken at 100 meters. 

 Frequency, 2 per cent at station 86; average, 1.5 per cent. 



.Temperature, 24?07-25?ii (24^59); salinity, 36.02-36.22 

 (36.12); density, 24.25-24.41 (24.33); pH, 8.23-8.25 (8.24). 



Xystonellopsis ornata (Brandt) Kofoid and Campbell 



(Figure 6g) 



Xystoncllopsis ornata, Kofoid and Campbell, 1929, p. 249, fig. 

 463. 



The rather large lorica, with remarkable spool-like upper 

 differentiation, conical bowl, and lower dagger-like mass, 

 has a length of 3.8 oral diameters. The oral rim is erect, 

 thin, and sharp. The upper bowl has unique differentiation 

 (analogous with that of Stelidiella simplex and partially with 

 that of Epicranella bella). There is a narrow angular ledge 

 (1.16 oral diameters) within the anterior 0.05 oral diameter, 

 followed by a wider angular but narrowed one (1.45 oral 

 diameters) at 0.84 oral diameter below the rim. The spool- 

 like region thus formed has 12 vertical, sinuous, equidistant 

 ribs, which arise from the upper surface of the wide ledge 

 and run decurrendy to just below the upper ledge; these ribs 

 subdivide the upper bowl into 12 curved, subequal facets. 

 The bowl contracts (19°) subconically for about 0.42 total 

 length below the lower ledge and at the lower end has a 

 diameter of approximately 0.5 oral diameter; its anterior 

 diameter just below the wide ledge is 0.84 oral diameter. 

 The remaining 0.38 total length is an irregular, dagger-like 

 mass homologous with the pedicel and the lance of other 

 species of Xystonellopsis. This mass spreads out (20°) to 

 0.55 oral diameter near 0.8 oral diameter from the aboral 

 tip, and below that level is more or less regularly reduced 

 subconically (42°) to the sharply pointed aboral tip. The 

 aboral end is minutely open. 



The wall reaches almost 0.28 oral diameter in thickness 

 across the lower ledge, but its average thickness is hardly 

 0.05. There are thin laminae and enclosed faint radial 

 secondary prisms. The wall thickens up in the aboral 0.38 

 total length and leaves a narrow canal to descend to the open 

 tip; the canal has a widened region at about 0.75 of its 

 length. The secondary alveoles of this posterior region are 

 in several layers and are hexagons. The lumen does not 

 enter the ledges, being generally conical. The surface has a 

 clear but faint hexagonal mesh work. 



The animal is rather small and has 2 macronuclei. 



Length, 262(^1. 



