TAXONOMY AND DISTRIBUTION 



101 



margin is sharp-edged. The upper bowl is cylindrical, 0.6 

 total length in length, and slightly concave, and increases in 

 diameter to 1.02 oral diameters aborally. The lower howl is 

 conical (32°) above, and expands to a blunt, angled ring at 

 0.87 total length from the rim; this ring has a diameter of 

 1.52 oral diameters. The aboral region is dishpan-shaped, 

 with a trace of aboral flattening. 



The wall reaches a thickness of 0.18 oral diameter near 

 the ring, is less than 0.09 aborally, and in the upper bowl 

 averages about 0.08. There arc thin laminae and enclosed 

 hyaline matter. 



Length, 109 to 1 19(1. 



Amplectellopsis angularis differs from ./. biedermanm 111 

 lacking a ring on the cylinder. 



Recorded from two stations, as follows: one (50) in the 

 South Pacific middle latitudes, and one (87) in the region oi 

 South Pacific island fields. 



Both records are from pump samples taken at 100 meters. 

 Frequency, minimum. 



Temperature, 20?57 in both; salinity, 55.73-36.02 (35.87); 

 density, 24.41-25. 18 (24.71)); pH, 8.22-8.23 (8.22s). 



CRICUNDELLA Kofoid and Campbell 

 Cricundella Kofoid and Campbell, 1929, p. 256. 



Cricundella is one of the more unusual genera of Tintin- 

 noina, being characterized especially by the numerous rings 

 on the thimble-like bowl. The oral rim is simple, as in 

 Undella and Amplectella. Cricundella is found close to the 

 equator in mid-ocean. 



One species is described here. 



Cricundella quadridivisa Kofoid and Campbell 



Cricundella quadridivisa Kofoid and Campbell, 1929, pp. 257- 

 258, fig. 497. 



The lorica has a length of 2.66 to 3.22 oral diameters, and 

 is subcylindrical, with four rings and a contracted aboral 

 cone. The oral margin is thin and smooth. The generally 

 cylindrical bowl has rings at o.n, 0.32, 0.47, and 0.63 total 

 length below the margin. Of these rings, the first has a 

 diameter of 1.19 oral diameters, and the others are wider, 

 being respectively 1.29, 1.30, and 1.27 oral diameters. The 

 cylinder itself has a subuniform diameter of less than 0.3 

 total length, or just a trifle greater than the diameter of the 

 oral rim. The aboral two-fifths of the bowl contracts at once 

 below the lowermost ring, at first as an inverted, somewhat 

 convex conical section (6o°) which is 0.18 total length in 

 length; below this it again rather more abruptly contracts 

 into a narrower, slender subconical (18 ), more or less tube- 

 like section, which has a length of about 0.19 to 0.29 total 

 length and a diameter of 0.33 oral diameter. The aboral 

 end is squarely truncated or imperceptibly convex. 



The wall is hyaline, with thin laminae, and the lumen is 

 cylindrical, not entering into the swollen rings. 



Length, 108 to 13311. 



Cricundella quadridivisa has four rings, instead of two 

 like C. tridivisa, but otherwise bears a close resemblance to 

 that species. Its aboral end is generally contracted subconical, 



unlike that of C. quadricincta, which has a hemispherical 

 aboral end. 



Recorded from two stations (54. 64) in the South Pacific 

 middle latitudes. 



There are 1 pump and 1 net sample, taken at 50 and 100 

 meters respectively. Frequency, 2 per cent at station 54. 



Temperature, I7?51-l8?74 (l8?l2); salinity. 54.58-35.35 

 I :;4.ii<>); density, 25.09-25.37 (25.23); pi I, 8.12-8.16 ( S. 1 4 ). 



ProplecTELLINAE, new subfamily 



The Proplcctellinae include only the genus Proplectella, in 

 which there is an inner collar. 



PROPLECTELLA Kofoid and Campbell 

 Proplectella Kofoid and Campbell, 1929, pp. 272-273. 



The inner collar is an unusual and peculiar character which 

 sets Proplectella apart from other genera. The wall structure, 

 general form, and oral and aboral ends show the relationship 

 to the other genera. 



Proplectella extends its range from the warmer parts of 

 the tropical ocean, where it often occurs in deeper than sur- 

 face water, and reaches cooler seas to the northward, where 

 a few species are found in distinctly cold water. It may be 

 regarded as one of the dominant genera of Tintinnoina, for 

 one or more species seldom fail to occur in any temperate 

 water. 



Twenty-three species are described here, of which two are 

 new. 



Proplectella acuta (Jorgensen) Kofoid and Campbell 

 Proplectella acuta, Kofoid and Campbell, 1929, p. 273, fig. 545. 



The short, conical lorica has a length of 1.95 oral diam- 

 eters. The oral margin is sharp. The bowl expands (20 ) 

 to a diameter of 1.24 oral diameters at 0.39 total length below 

 the rim, and then contracts (21 ° anteriorly and 43 below, 

 finally 95 ). The aboral end is pointed. 



The wall reaches a maximum thickness of 0.14 oral diam- 

 eter. The inner collar is funnel-like (35°), with a length 

 of nearly 0.4 oral diameter, and the diameter at the lower 

 end is 0.9 oral diameter. There are thin laminae and en- 

 closed clear material. 



Length, 57 to 65P. 



Proplectella acuta suggests P. part/a and P. grandis in 

 shape, but is less contracted aborally than the former, and 

 smaller; from the latter species it differs in shortness, less 

 width, and less aboral fullness. Proplectella cuspidata is not 

 so full below, and is longer. 



Recorded from one station (19) in the Sargasso Sea, in a 

 net sample taken at 50 meters. Frequency, minimum. 



Temperature, 25?3i; salinity, 37.15; density, 24.89; pH, 

 8.27. 



Proplectella amphora Kofoid and Campbell 



Proplectella amphora Kofoid and Campbell, 1929, pp. 273-274, 



fig- 530. 

 The moderate-sized lorica, with six subequal sides and flat 

 aboral end, has a length of 1.9 oral diameters. The oral 



