100 



OCEANIC TINTINNOINA OF LAST CRUISE OF CARNEGIE 



and 1.7 and 5.1 per cent in Atlantic and Pacific net samples, 

 respectively. 



Temperature: Atlantic, net samples i9?82-25?3i (2i?83); 

 Pacific, pump samples i8?54-i8'?95 (i8?78), net samples 

 i5?03-20?49 (i8?65). Salinity: Atlantic, net samples 36.04- 

 37.15 (36.72); Pacific, pump samples 34.88-35.04 (34.98), 

 net samples 36.04-37.04 (36.72). Density: Atlantic, net 

 samples 24.89-26.07 (25.15); Pacific, pump samples 24.24- 

 25.44 (25-30), net samples 24.96-25.18 (25.07). pH: At- 

 lantic, net samples 8.14-8.27 (8.23); Pacific, pump samples 

 8.01-8.32 (8.20), net samples 8.18-8.39 (8-3o)- 



Amplectella monocollaria (Laackmann) Kofoid 

 and Campbell 



Amplectella monocollaria, Kofoid and Campbell, 1929, p. 253, 

 fig. 489. 



The rather long lorica, with one ring on upper cylinder 

 and wide, flattened lower bowl, has a length of 2.13 oral 

 diameters. The oral margin is thin and sharp. The upper 

 bowl or cylinder (0.79 total length in length) has a ring 1.64 

 oral diameters in diameter at 0.42 total length from the rim. 

 The ring is sharply angular (90°), and the bowl flares 

 widely (75°) below, until it meets the upper end of the 

 lower bowl; the diameter at this level is 1.71 oral diameters. 

 The lower bowl is low and panlike, with a height only 0.31 

 of the diameter. The aboral end is flattened. 



The wall has a thickness of 0.18 oral diameter at the 

 junction of upper and lower bowls, and elsewhere is much 

 thinner. There are hyaline laminae and enclosed clear 

 material. The lumen enters but little into the ring. 



Length, i20[,i. 



Amplectella monocollaria differs from A. occidentalis in 

 the shape of the aboral region, and from all other species of 

 the genus in the presence of but a single ring on the cylinder. 



Recorded from fifteen stations, one in the Atlantic and 

 fourteen in the Pacific, as follows: one (20) in the Sargasso 

 Sea, four (54, 55, 56, 60-61) in the South Pacific middle 

 latitudes, seven (133, 134, 136, 146, 147, 148, 149) in the 

 California region, two (141, 142) in the North Pacific middle 

 latitudes, and one (150) in the North Pacific trade region. 

 This species is closely associated with Amplectella collaria in 

 its distribution. 



There are 6 pump and 10 net samples, of which i was 

 taken at the surface and 15 at 100 meters. Maximum fre- 

 quency, 6 per cent at stations 146, 147; other records above 

 minimum (2 to 4 per cent) from stations 54, 55, 136, 141, 

 148; averages, 1.5 loricae in Pacific pump samples, and 3.1 

 and i.o per cent in Atlantic and Pacific net samples, respec- 

 tively. 



Temperature: Atlantic, net sample 26^56; Pacific, net 

 samples i6?75-20?49 (19? 17), pump samples i6?90-20?79 

 (i8?43). Salinity: Adantic, net sample 36.73; Pacific, net 

 samples 34.32-35.35 (34.38), pump samples 34.47-35.10 

 (34.78). Density: Adantic, net sample 25.38; Pacific, net 

 samples 24.24-25.48 (24.36), pump samples 24.46-25.37 

 (24.94). pH: Adantic, net sample 8.19; Pacific, net samples 

 8.08-8.39 (8.27), pump samples 8.11-8.39 (8.29). 



Amplectella occidentalis Kofoid and Campbell 



Amplectella occidentalis Kofoid and Campbell, 1929, p. 254, 

 fig. 487. 



The moderate-sized lorica, with one ring and pointed 

 lower bowl, has a length of 2.2 oral diameters. The oral 

 margin is thin-edged. The upper bowl is a cylinder (0.77 

 total length in length) with one ring of 1.3 oral diameters at 

 0.36 total length below the rim. The lower end of the 

 cylinder spreads (63°) with slightly convex sides to a diam- 

 eter of 1.5 oral diameters at its lower end. The lower bowl 

 is broad, short, and angled (110°), and the aboral end is 

 bluntly pointed. 



The wall reaches nearly 0.2 oral diameter in thickness in 

 the upper part of the lower bowl, but is elsewhere thinner. 

 There are thin laminae and included hyaline matter. The 

 lumen fails to enter the ring. 



Length, loi to lojyi. 



Amplectella occidentalis resembles A. praeacuta in its 

 pointed aboral end, but has only a single ring instead of two. 



Recorded from one station (78) in the Galapagos region, 

 in a pump sample taken at 100 meters. Frequency, mini- 

 mum. 



Temperature, 22?04; salinity, 36.17; density, 25.11; pH, 

 8.14. 



Amplectella praeacuta Kofoid and Campbell 



Amplectella praeacuta Kofoid and Campbell, 1920, p. 254, fig. 

 491. 



The moderately tall lorica, with two rings and cordate 

 lower bowl, has a length of 2.25 oral diameters. The oral 

 margin is sharp. The upper bowl is a cylinder (0.64 total 

 length in length), with the upper ring of 1.29 oral diameters 

 at 0.26 total length below the margin, and the second ring 

 of 1.33 at 0.47; both rings are angular (87°). The lower 

 bowl has a length of 0.27 of its own maximum diameter 

 (1.5 oral diameters), and is angled (150°) aborally. 



The wall averages o.i oral diameter in thickness, being 

 thickest above the lower bowl. There are thin laminae and 

 enclosed dense matter. 



Length, 106(^1. 



Amplectella praeacuta has a pointed aboral end like that 

 of A. occidentalis, but has two rings instead of one. 



Recorded from one station (45) in the Galapagos region, 

 in a net sample taken at 100 meters. Frequency, minimum. 



Temperature, 2i?69; salinity, 35.21; density, 24.48; pH, 



7-77- 



AMPLECTELLOPSIS Kofoid and Campbell 



AmplcctcUopsis Kofoid and Campbell, 1929, p. 255. 

 This is a rare tropical genus, diflering from Amplectella 

 in lacking rings and internal bulge. 

 One species is described here. 



Amplectellopsis angularis Kofoid and Campbell 

 Amplcctellopsis angularis Kofoid and Campbell, 1929, pp. 255- 



256, fig. 493. 

 The moderate-siz.ed lorica. without ring and with angled 

 lower bowl, has a length of 2.2 oral diameters. The oral 



