TAXONOMY AND DISTRIBUTION 



123 



which occupies approximately 0.37 total length, the shaft 

 contracts to a diameter of 0.55 oral diameter at 0.36 oral 

 diameter above the aboral end. The aboral flare (18°) meets 

 the thin, brimless, open aboral end. 



The wall is thin and hyaline. 



Length, 192 to 254^1. 



Eiitintinniis medius differs from E. turgescens in having 

 aboral flare. It is stouter and longer than E. elegans and 

 has less constriction toward the aboral end of the shaft. It 

 is much like E. latus, but is smaller and narrower. 



Recorded from seventeen stations, three in the Atlantic 

 and fourteen in the Pacific, as follows: one (16) in the Gulf 

 Stream, two (18, 21) in the Sargasso Sea, two (45, 46) in 

 the Galapagos region, one (48) in the region of South 

 Pacific island fields, six (103, 104, 109, 138, 150, 151) in the 

 North Pacific trade region, two (142, 144) in the North 

 Pacific middle latitudes, and three (146, 147, 148) in the 

 California region. 



There are 14 pump and 6 net samples, of which 5 were 

 taken at the surface, 6 at 50 meters, and 9 at 100 meters. 

 Maximum frequency, 2 per cent at stations 45, 46, 48; in 

 pump samples there were i to 8 loricae; average in Pacific 

 net samples 1.6 per cent, in pump samples 1.4 loricae. 



Temperature: Atlantic, net sample 23?64, pump samples 

 22?i2-26?57 (24?34); Pacific, i9?27-23?63 (2i?55) and 

 i7?46-25?45 (2i?82), respectively. Salinity: Atlantic, net 

 sample 36.41, pump samples 36.28-36.82 (36.55); Pacific, 

 34.63-36.44 (35.29) and 34.42-35.32 (34.88), respectively. 

 Density: Atlantic, net sample 23.64, pump samples 22.12- 

 26.57 (24.34); Pacific, 24.11-24.86 (24.57) and 22.89-25.11 

 (24.17), respectively. pH: Atlantic, net sample 8.23, pump 

 samples 8.24-8.32 (8.28); Pacific, 8.12-8.32 (8.20) and 8.18- 

 8.37 (8.28), respectively. 



Eutintinnus pacificus Kofoid and Campbell 



Tintinniis pticificiis Kofoid and Campbell, 1929, p. 337, fig. 632; 

 Marshall, 1934, p. 659, fig. 41. 



The short, truncate subconical lorica, with little brim and 

 wide-open aboral end, has a length of 2.3 oral diameters. 

 The thin oral margin has only a thickened, molded brim. 

 The shaft tapers (6°) and in some loricae is contracted in 

 the postmedian half. The aboral end has a diameter of 

 nearly 0.67 oral diameter. It is rimless. 



The wall is nearly transparent and of exceeding thin- 

 ness. 



Length, 67 to 7i|.t. 



Marshall's (1934) loricae are posteriorly contracted and 

 also longer (108 to 1201.1) than the Carnegie specimens. 



Eutintinnus pacificus is shorter than E. pinguis (114 to 

 i6i|^i) and also stouter (length 2.3 as against 2.6 to 3.8 oral 

 diameters); it lacks the median bulge which characterizes 

 pinguis. Both species differ from E. tubulosus in being rela- 

 tively stouter. 



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

 in a net sample taken at the surface. Frequency, 2 per cent. 



Temperature, 22?43; salinity, 35.26; density, 24.31; pH, 



Eutintinnus perminutus Kofoid and Campbell 



Tintinnus pcnniniitiis Kofoid and Campbell, 1929, p. 337, fig. 

 649. 



The fairly short lorica, with tapering shaft, bare median 

 bulge, and both ends flaring, has a length of 4.37 oral diam- 

 eters. The oral margin has a narrow, molded brim. The 

 upper end of the shaft flares (38°) well within o.i oral 

 diameter, then tapers (4°) for over half its length. Below 

 this level it contracts very slightly to the aboral end, which, 

 like the upper end, flares (38°) within o.i oral diameter. 

 The open aboral end has no brim and is 0.65 oral diameter 

 in diameter. 



The wall is uniformly thin and clear. 



Length, 140 to 183(1. 



Eutintinnus perminutus resembles E. macilentus , but that 

 species is sweepingly concave laterally. It is also close to 

 E. tubulosus, but in that species there are no oral and aboral 

 flares. Other smaller species are not likely to be confused 

 with it. 



Recorded from seven stations, one in the Atlantic and six 

 in the Pacific, as follows: one (19) in the Sargasso Sea, two 

 (77, 80) in the Galapagos region, one (81) in the region of 

 South Pacific island fields, two (112, 141) in the North 

 Pacific middle latitudes, and one (135) in the California 

 region. 



There are 3 pump and 4 net samples, of which 2 were 

 taken at the surface, 3 at 50 meters, and 2 at 100 meters. 

 Frequency, 3 per cent at station 77; other records above 

 minimum (2 per cent) from stations 80, 81; average in 

 Pacific net samples, 2.3 per cent. 



Temperature: Atlantic, net sample 23^31; Pacific, net 

 samples 23?72-26?42 (25?5o), pump samples i8?95-23?25 

 (20?99). Salinity: Atlantic, net sample 37.15; Pacific, net 

 samples 35.85-36.04 (35.94), pump samples 34.60-35.10 

 (34.86). Density: Atlantic, net sample 24.89; Pacific, net 

 samples 23.56-24.53 (23.94), pump samples 23.58-24.96 

 (24.06). pH: Atlantic, net sample 8.27; Pacific, net samples 

 8.19, pump samples 8.22-8.34 (^-29). 



Eutintinnus pinguis Kofoid and Campbell 



Tintinnus pinguis Kofoid and Campbell, 1929, p. 338, fig. 640. 



The small, stout lorica has a median bulge, an indefinite 

 suboral flare, and a length of 3.0 oral diameters. The thin 

 oral margin has a narrow, molded brim. There is a bare 

 suboral flare. The shaft tapers (10°), but has some bulge 

 (0.87 oral diameter) near its middle. Below the bulge it 

 contracts regularly to the open aboral end; the aboral diam- 

 eter is 0.63 oral diameter. The aboral end is brimless. 



The hyaline wall is exceedingly thin. 



Length, 114 to 161(1. 



Eutintinnus pinguis differs from E. pacificus in being 

 longer and more slender, and in having a median bulge. It 

 lacks the aboral cylinder of E. apertus and the flare of E. 

 procurrerens. 



Recorded from four stations, two each in the Atlantic and 

 the Pacific, as follows: one (21) in the Sargasso Sea, one 



