TAXONOMY AND DISTRIBUTION 



99 



Recorded from four stations in the Pacific, as follows: one 

 (67) in the South Pacific middle latitudes and three (75, 77, 

 78) in the Galapagos region. 



There are 4 net samples, of which 1 was taken at the 

 surface, 1 at 50 meters, and 2 at 100 meters. Frequency, 2 

 per cent at station 75; average, 1.2 per cent. 



Temperature, i6?36-24?38 (20?7i); salinity, 34.70-36.04 

 (35.56); density, 24.33-25.55 (24.96); pH, 8.09-8.19 (8.13). 



Undella pistillum kofoid and Campbell 

 Undella pistillum Kofoid and Campbell, 1929, p. 265, fig. 500. 



The moderate-sized lorica, with wide, flattened aboral 

 region, has a length of 2.5 oral diameters. The oral margin 

 is sharp. The bowl increases evenly and constantly (15°) 

 in diameter from the rim to the aboral end, where its diam- 

 eter is 1.5 oral diameters. The aboral end is decidedly flat- 

 tened, but rounds over from the widest level without angu- 

 lation. 



The wall has a thickness of 0.12 oral diameter a little (0.5 

 oral diameter) below the rim, and frequently thins in the 

 lower bowl. There are thin laminae and enclosed hyaline 

 material. 



Length, 90 to 120U.. 



Undella pistillum bears slight resemblance to other species, 

 although suggestive of Amplectellopsis angularis save that it 

 has no suddenly swollen angular aboral region. 



Recorded from one station (145) in the North Pacific 

 middle latitudes, in a net sample taken at 50 meters. Fre- 

 quency, 2 per cent. 



Temperature, 19? 16; salinity, 34.32; density, 24.48; pH, 

 8.34. 



Undella turgida Kofoid and Campbell 



Undella turgida Kofoid and Campbell, 1929, p. 266, fig. 502. 



The extremely short, wide lorica, with convex-conical bowl 

 and thick wall, has a length of 1.25 oral diameters. The 

 oral rim is thin, and formed by the upward-directed inner 

 lamina, so that there is a slight shoulder at the outer edge. 

 The convex bowl swells evenly to a diameter equal to that of 

 the length of the whole lorica at the ledge. Below this level 

 it contracts evenly and regularly, being strongly globose. 

 The aboral end is barely pointed. 



The wall is thickest suborally (0.06 oral diameter), and 

 thins evenly to the aboral end. The laminae are fairly thick 

 and enclose homogeneous material. 



Length, 41 to 45U.. 



Undella turgida resembles U. hemispherica, but its pro- 

 portions are different, and its wall is thicker suborally and 

 thins down rather than remaining thick. The lip is also 

 different. In some ways it recalls some species of Proplec- 

 tella, as claparedei, but it never has an inner collar or a con- 

 tracted oral opening. 



Recorded from five stations in the Pacific, as follows: two 

 (45, 46) in the Galapagos region and three (81, 84, 85) in 

 the region of South Pacific island fields. 



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

 taken at the surface and 4 at 50 meters. Frequency, 6 per 



cent at station 84, 4 per cent at station 85; average in net 

 samples, 3.6 per cent. 



Temperature: pump samples 22?43~23?26 (22^84), net 

 samples 26?42-27?89 (2j°.2y). Salinity: pump samples 

 35.26-35.33 (35.29), net samples ^^S-36.42 (36.17). Den- 

 sity: pump samples 24.13-24.31 (24.22), net samples 23.38- 

 23.64 (23.52). pH: pump samples S. 12-8. 16 (8.14), net 

 samples 8.19-8.22 (8.21). 



AMPLECTELLA Kofoid and Campbell 



Amplectella Kofoid and Campbell, 1929, p. 251. 



Amplectella is a tropical genus of considerable differentia- 

 tion. It is usually rather rare. 

 Four species are described here. 



Amplectella collaria (Brandt) Kofoid and Campbell 



(Figure 81) 



Amplectella collaria, Kofoid and Campbell, 1929, p. 253, fig. 

 488. 



The moderately tall, stout lorica, with two rings on the 

 cylinder, and with hemispherical aboral end, has a length of 

 2.09 oral diameters. The oral margin is rounded over. The 

 upper bowl is cylindrical, 0.76 total length in length, and 

 with two rings. These rings, each with a diameter of 1.3 

 oral diameters, are at 0.3 and 0.48 total length from the rim; 

 both are narrow angular. The wall between them is sweep- 

 ingly concave. The lowermost of the three sections of the 

 cylinder especially spreads. The diameter of the lower end 

 of the cylinder is 1.57 oral diameters. The lower bowl is 

 broadly rounded, its height being 0.4 its own diameter. The 

 aboral end is unmodified. 



The wall has a thickness of over 0.08 oral diameter in the 

 cylinder and a trifle less aborally. There are thin laminae 

 and enclosed hyaline material. 



Length, 81 p. 



The Carnegie loricae are stouter than is usual for this 

 species, and also somewhat shorter. 



Amplectella collaria differs from A. ampla in longer 

 cylinder, greater lateral concavities, and angular, shorter 

 bowl. Amplectella praeacuta has a cordate bowl, and A. 

 monocollaria has but one ring on the cylinder. 



Recorded from fourteen stations, four in the Atlantic and 

 ten in the Pacific, as follows: three (17, 18, 19) in the Sar- 

 gasso Sea, one (23) in the Atlantic equatorial region, three 

 (55, 65, 67) in the South Pacific middle latitudes, six (135, 

 136, 146, 147, 148, 149) in the California region, and one 

 (150) in the North Pacific trade region. The distribution 

 of Amplectella collaria and of A. monocollaria is much 

 alike; there are seven stations at which they occur together, 

 and the other stations are closely adjacent. 



There are 3 pump samples and 14 net samples, of which 

 5 were taken at 50 meters and 12 at 100 meters. The absence 

 of A. collaria at the surface is worthy of note. Maximum 

 frequency, 8 per cent at station 147; other records above 

 minimum (2 to 7 per cent) from stations 18, 19, 65, 67, 146, 

 148, 149, 150; averages, 1.0 lorica in Pacific pump samples, 



