6 4 



OCEANIC TINTINNOINA OF LAST CRUISE OF CARNEGIE 



There are 2 pump and 7 net samples, of which 1 was taken 

 at the surface, 6 at 50 meters, and 1 each at 100 and 150 

 meters. Maximum frequency, 11 per cent at station 84; 

 other records above minimum (2 to 7 per cent) from stations 

 45, 83, 84; averages, 4.4 per cent and 1.5 loricae in net and 

 pump samples, respectively. 



Temperature: pump samples i4?73~27?46 (2i?oo), net 

 samples 2i?6o-27?89 (24?7o). Salinity: pump samples 

 34.27-36.4g (35.38), net samples 34.71-36.42 (35.48). Den- 

 sity: pump samples 23.11-25.48 (24.59), net samples 22.31- 

 24.48 (23.79). pH: pump samples 8.12-8.24 (8.18), net 

 samples 8.12-8.22 (8.16). 



Rhabdonellopsis longicaulis Kofoid and Campbell 

 (Figure 88) 

 Rhabdonellopsis longicaulis Kofoid and Campbell, 1929, p. 223, 



fig. 419. 

 The greatly elongated lorica, with heavy knob, minute, 

 sparse fenestrae, and very long pedicel, has a length of 8.0 

 oral diameters. The oral margin is fairly high, ringlike, and 

 erect, and is the inner boundary of the concave suboral 

 trough. The outer margin of the trough is serrate, and its 

 diameter is 1.24 oral diameters. The bowl flares (52 ) 

 within the anterior 0.32 oral diameter, and then tapers (13 ) 

 for 0.42 total length before becoming subconical (33°) for 

 0.72 oral diameter. From the lower end of this section arises 

 the tapering pedicel (5 ), the length of which is 0.42 total 

 length, and the diameter of which is 0.16 oral diameter. At 

 the aboral end of the pedicel is the thickened, expanded knob 

 (0.25 oral diameter in width). From the end of the knob 

 arises the thin lance, the length of which is 0.6 oral diameter. 

 The wall reaches nearly 0.1 oral diameter in thickness sub- 

 orally and lessens to a fraction in the lower bowl and pedicel. 

 There are thin laminae which enclose minute prisms. The 

 ribs are few (16), rarely branched within the upper fourth, 

 continued down to the knob, nearly vertical, decurrent sub- 

 orally, and not equally spaced. There are 2 to 5 minute 

 fenestrae scattered in the intercostal spaces; these are the 

 sites of tiny coccoliths. The knob is brownish, but the rest 

 of the lorica is translucent. 

 Length, 350 to 468^. 



This large, stately species is easy to distinguish from the 

 others. The length, few fenestrae, long pedicel, heavy knob, 

 and few ribs are all characters that separate it. 



Recorded from nineteen stations in the Pacific, as follows: 

 five (45, 46, 75, 76, 77) in the Galapagos region, two (63, 

 65) in the South Pacific middle latitudes, two (82, 84) in the 

 region of South Pacific island fields, six (103, 107, 108, 109, 

 140, 151 ) in the North Pacific trade region, one (135) in the 

 California region, one (141) in the North Pacific middle 

 latitudes, and two (152, 153) in the Pacific equatorial region. 

 There are 21 pump and 12 net samples, of which 16 were 

 taken at the surface, 11 at 50 meters, and 6 at 100 meters. 

 Maximum frequency, 40 per cent at station 151; other records 

 above minimum (2 to 19 per cent) from stations 45, 75, 76, 

 77, 84, 152; average in net samples, 8.4 per cent; in pump 

 samples, maximum, 6 loricae at station 45; average, 1.7. 



Temperature: pump samples i5?o3-28?o8 (23^43), net 

 samples n?48-27?52 (22^56). Salinity: pump samples 

 34.02-35.86 (34.87), net samples 34.02-36.42 (35.43). Den- 

 sity: pump samples 21.78-25.48 (23.20), net samples 22.34- 

 26.50 (24.34). pH ; pump samples 8.08-8.47 (8.24), net 

 samples 7.76-8.21 (8. 11). 



Rhabdonellopsis minima Kofoid and Campbell 

 Rhabdonellopsis minima Kofoid and Campbell, 1929, p. 224, 

 fig- 4^3- 



The rather short lorica, with cornucopia-shaped bowl, 

 long, tapering pedicel, and spindle-shaped knob, has a length 

 of 5.0 oral diameters. The oral rim is submerged by the 

 higher outer edge of the suboral trough, and its diameter is 

 1.09 oral diameters. The bowl contracts as a cone (13 ) in 

 the anterior 0.27 total length, and then (25 ) in similar form 

 and length. The long (0.49 total length), tapering pedicel 

 (15 ) has a thickened spindle-like knob (0.11 oral diameter 

 in length), below which is a short lance the length of which 

 is about equal to that of the knob. 



The wall reaches a thickness of 0.1 oral diameter suborally 

 and progressively lessens lower in the bowl and pedicel. 

 There are thin laminae which enclose minute alveoles. The 

 ribs arise a little below the suboral trough, are commonly 

 bifurcate in the upper part, are decidedly left-turning (as 

 much as 20 ), continue to the knob and lance, and number 

 about 16. Fenestrae (6 to 18) are found in the intercostae, 

 as are also minute prisms. 



Length, 177 to 254(^1. 



Rhabdonellopsis minima has a conical bowl, more twisted 

 striae, and spindle-shaped knob, unlike R. intermedia. 

 Rhabdonellopsis triton is much narrower, with a different 

 number of ribs and different bowl. The remaining species 

 have skirted knobs. 



Recorded from eight stations in the Pacific, as follows: 

 one (37) in the Pacific equatorial region, five (52, 54, 61, 

 62-63, 64) in the South Pacific middle latitudes, and two 

 (48, 81) in the region of South Pacific island fields. 



There are 2 pump and 11 net samples, of which 11 were 

 taken at the surface and 2 at 100 meters. Maximum fre- 

 quency, 98 per cent at station 48, minimum at station 52; 

 average in net samples, 25 per cent; only 3 loricae were in 

 pump samples. 



Temperature: pump samples 26?53~27?i2 (26?82), net 

 samples io?92-23?63 (i9?53). Salinity: pump samples 

 31.68-35.82 (33.75), net samples 34.05-36.44 (35.15). Den- 

 sity: pump samples 20.20-23.50 (21.85), net samples 24.33- 

 26.06 (24.65). pH: pump samples 8.19-8.28 (8.23), net 

 samples 8.03-8.27 (8.15). 



Rhabdonellopsis triton (Zacharias) Kofoid and Campbell 

 (Figure 86) 



Rhabdonellopsis triton, Kofoid and Campbell. i<)20, p. 224, 



fig. 422. 

 Rhabdonella spiralis, Hofker (part), 1931, pp. 378-381, fig. 67 



(for figs. 68-73 see Rhabdonella spiralis). 



The relatively short lorica, with conical bowl, swollen, 



