62 



OCEANIC T1NTINNOINA OF LAST CRUISE OF CARNEGIE 



Maximum frequency, 78 per cent at station 20-21; other 

 records above minimum (2 to 60 per cent) from stations 21, 

 22, 23, 24, 25, 27, 28, 29, 30, 32, 33, 34, 68, 69, 80, 99, 136, 

 137, 145, 152, 153, 154, 159; averages in net samples, 17.9 

 and 4.8 per cent for the Atlantic and Pacific, respectively; in 

 pump samples, 150 loricae at station 96; average in Pacific 

 pump samples, 10.3. 



Temperature: Atlantic, pump samples i4?6o-27?6i (23? 1 1 ), 

 net samples i4?6o-28?5 4 (23?54); Pacific, i5?84-29?43 

 (23?68) and n?48-28?6o (ai?47), respectively. Salinity: 

 Atlantic, pump samples 35.22-36.75 (35.96), net samples 

 35.61-36.65 (36.13); Pacific, 33.68-35.39 (35.08) and 34.30- 

 35.95 (34.96), respectively. Density: Atlantic, pump samples 

 22.84-26.62 (24.43), net samples 21.78-26.02 (23.49); Pacific, 

 21.70-25.48 (23.45) and 22.31-26.50 (24.31), respectively. 

 pH: Atlantic, pump samples 7.93-8.32 (8.20), net samples 

 7.93-8.32 (8.19); Pacific, 8.08-8.47 (8.29) and 7.76-8.39 

 (8.16), respectively. 



Rhabdonella torta Kofoid and Campbell 

 Rhabdonella torta Kotoid and Campbell, 1929, p. 220, fig. 404. 



The fairly long lorica, with stout, chalice-shaped bowl, 

 oblique ribs, and wide conical horn, has a length of 4.0 oral 

 diameters. The oral rim is submerged and low. The sub- 

 oral trough is flat and the diameter of its outer rim is 1.18 

 oral diameters. The bowl tapers (15°) in the anterior two- 

 thirds and becomes subconical (30 ) in the lower section. 

 The aboral horn is conical (22 ), little differentiated, and 

 about 0.3 total length in length, and has a blunted, free tip. 



The wall reaches 0.11 oral diameter in thickness suborally 

 and thins regularly in the bowl. There are thin laminae and 

 enclosed alveoles in several layers. There are 56 right-twisted 

 (upwards of 40 ), feebly anastomosed and branched ribs; 

 the tips of the ribs are left-turned near the suboral margin. 

 There are 4 to 8 distinct fenestrae in the intercostae. The 

 lorica, as in Rhabdonella lohmanni and R. hensem, is deep 

 brown. 



Length, 210 to 228U.. 



Rhabdonella torta is related to R. henseni and R. lohmanni, 

 but is much shorter than either and has a much less clearly 

 differentiated horn. The ribs are also different. 



Recorded from station 61 in the South Pacific middle lati- 

 tudes, in a net sample taken at the surface. Frequency, 4 

 per cent. 



Temperature, i6?9o; salinity, 34.05; density, 24.83; pH, 

 8.05. 



Rhabdonella valdestriata Brandt 



(Figure 91) 



Rhabdonella valdestriata. Kofoid and Campbell, 1929, p. 220, 

 fig. 410. 



The moderately tall, chalice-shaped lorica, with almost no 

 suboral flare, slight transition between bowl and horn, and 

 long bowl, has a length of 4.25 oral diameters. The oral rim 

 is ringlike and submerged by the higher rim of the suboral 

 trough. The suboral trough is very shallow and the diam- 

 eter of its outer edge is 1.2 oral diameters. The bowl tapers 



(12 ) for 0.34 total length, then becomes inverted subconical 

 (28 ) for 0.29. The transition between lower bowl and 

 aboral horn is gradual. The horn is conical (15°), is 0.37 

 total length in length, and has a sharp, pointed free tip. 



The wall is thickest suborally (0.12 oral diameter) and 

 thins evenly below. There are thin laminae with enclosed 

 minute alveoles in several layers. There are 24 vertical, 

 continuous, rarely branched and anastomosed ribs with 

 scattered, irregularly placed fenestrae. 



Length, 150 to 225(1. 



Rhabdonella valdestriata differs from R. cuspidata in its 

 longer bowl, lack of aboral swelling, and shortness. It is less 

 widely conical than R. striata and lacks the distinct suboral 

 flare of R. spiralis. 



Recorded from three stations in the Pacific, as follows: 

 one (35) in the Pacific equatorial region, one (49) in the 

 region of South Pacific island fields, and one (63) in the 

 South Pacific middle latitudes. 



There are 3 pump samples and 1 net sample, of which 2 

 were taken at the surface and 2 at 50 meters. Frequency, 

 4 per cent in the net sample; 4 to 60 (35.0) loricae in pump 

 samples. 



Temperature: pump samples i7?oi-23?38 (i9?92), net 

 sample i6?30. Salinity: pump samples 34.59-36.17 (35.13), 

 net sample 34.88. Density: pump samples 24.36-25.22 

 (24.76), net sample 25.60. pH: pump samples 8.07-8.27 

 (8.14), net sample 7.92. 



RHABDONELLOPSIS Kofoid and Campbell 

 Rhabdonellopsis Kofoid and Campbell, 1929, p. 221. 



Rhabdonellopsis probably arose from Rhabdonella by the 

 addition of a knob and lance. 



Rhabdonellopsis is a genus of the circumtropical region, 

 although some species range southward of New Zealand and 

 northward of Hawaii. Loricae are carried by the Gulf 

 Stream to considerable latitudes. 



Six species are described here. 



Rhabdonellopsis apophysata (Cleve) Kofoid and Campbell 



Rhabdonellopsis apophysata. Kofoid and Campbell, 1929, p. 

 221, fig. 420. 



The relatively elongated lorica, with stout skirt, ribbed 

 pedicel, and no fenestrae, has a length of 6.4 oral diameters. 

 The oral rim is high, ringlike, and erect, and forms the inner 

 boundary of the suboral trough. The trough is flat, and its 

 outer rim has a diameter of 1.3 oral diameters. The long 

 bowl flares (54°) within the upper 0.4 oral diameter. Below 

 the flaring region the bowl is subconical (15 in the upper 

 0.35 total length and 32 in the lower section). At its lower 

 end is the narrow (0.21 oral diameter), cylindrical pedicel, 

 the length of which is 0.41 total length. At its aboral end is 

 the expanded skirt, the lower edge of which is irregular, and 

 from its middle arises the conical (io°) pointed lance. 



The wall is thickest just below the suboral trough, where 

 it reaches 0.12 oral diameter. It becomes much thinner 

 below. There are thin laminae with enclosed radial, single- 



