TAXONOMY AND DISTRIBUTION 



37 



Dictyocysta reticulata is shorter and has a longer bowl 

 than D. grandis; it has no aboral point like D. mexicana; 

 and its howl is more angled at the shoulder than is that of 

 D. lata. Most of the remaining species either are of the D. 

 mitra type, or else have 2 rows of clear-cut windows in the 

 collar. This species is by far the most common in warm 

 water. 



Recorded from forty-seven stations, seventeen in the 

 Atlantic and thirty in the Pacific, as follows: three (2, 14. 

 [6) in the Gulf Stream, three (3, 4, 5) in the Atlantic drift, 

 two ( t8, 19) in the Sargasso Sea, seven (22, 23, 24, 25, 26, 

 28, 30) in the Atlantic equatorial region, two (33, 34) in the 

 Caribbean Sea, five (35, 35-36, 36, 37, 154) in the Pacific 

 equatorial region, tweb'e (40, 41, 42, 44, 45, 47, 69, 71, 77, 

 78, 79, 80) in the Galapagos region, three (48, 84, 92) in the 

 region of South Pacific island fields, five (59, 62, 64, 65, 67) 

 in the South Pacific middle latitudes, two (109, no) in the 

 North Pacific trade region, one (in) in the North Pacific 

 middle latitudes, and two (133, 149) in the California region. 

 Dictyocysta reticulata is apparently absent only in cool 

 regions such as the North Sea, the American cold-water 

 region, the East Asiatic marginal sea, and the Alaskan 

 secondary region. 



There are 34 pump and 44 net samples, of which 19 were 

 taken at the surface, 31 at 50 meters, and 28 at 100 meters. 

 Maximum frequency, 13 per cent at station 77; other records 

 above minimum (2 to 11 per cent) from stations 2, 3, 22, 24, 

 25, 26, 28, 35, 35-36, 40, 41, 42, 44, 45, 47, 48, 59, 62, 65, 69, 

 78, 80, 154; averages, 1.0 and 2.1 loricae in Atlantic and 

 Pacific pump samples, and 2.8 and 4.1 per cent in Atlantic 

 and Pacific net samples, respectively. 



Temperature: Atlantic, pumpsamples i4?95~28?25 (23?46), 

 net samples i3?37~27?88 (20? 12); Pacific, i3?93~27?99 

 (2^23) and i4?33-27?52 (2^05), respectively. Salinity: 

 Atlantic, pump samples 29.70-37.15 (35.33), net samples 

 35.61-36.81 (36.15); Pacific, 31.62-36.17 (34.86) and 31.62- 

 36.44 (34.48), respectively. Density: Atlantic, pump samples 

 18.62-26.08 (23.89), net samples 23.26-27.01 (25.94); Pacific, 

 20.20-26.21 (24.37) ano - 20.34-26.17 (24.47), respectively. 

 pH: Atlantic, pump samples 8.14-8.31 (8.21), net samples 

 7.93-8.30 (8.16); Pacific, 7.85-8.37 (8.17) and 7.87-8.38 

 (8. n), respectively. 



Dictyocysta speciosa Jorgensen 

 Dictyocysta speciosa, Kofoid and Campbell, 1929, pp. 300-301, 

 fig- 575- 



The large lorica, with elegans-like fenestration and aborally 

 constricted bowl, has a length of 1.63 oral diameters. The 

 oral margin is mildly arched, with 8 flattened rims. The 

 collar (1.0 oral diameter in length) is subcylindrical, the 

 diameter at the lower end being 1.12 oral diameters. The 

 collar has a double row of fenestrae. The upper row is made 

 up of 8 rectangular windows with squarish corners, larger 

 than the 9 subpentagonal to square ones of the lower row. 

 The beams and mullions are hyaline and rounded, and en- 

 close the open windows. The bowl has a considerably 

 rounded shoulder, reaches 1.31 oral diameters a little below 



the lower end of the collar, then rapidly contracts (53°). and 

 becomes almost hemispherical (125 ) within its lower fourth. 

 The upper section is flat-sided. The aboral end is obtusely 

 blunted. 



The wall of the bowl has a postequatorial row oi 8 

 rather small round fenestrae, and a lower row ot 6 even 

 smaller oval ones. The interfencstral area has many small 

 circles of nearly uniform size. 



Length, 66 to 8op. 



Dictyocysta speciosa is larger than other species related to 

 D. elegans, and has a bowl shaped unlike those in the re- 

 mainder of that general group. Once seen, it is not hard 

 to recognize. 



Recorded from five stations (3, 4, 5-6, 6, 6-7) in the 

 Atlantic drift and the North Sea. 



Net samples only, of which 8 were taken at the surface, 2 

 at 50 meters, and 4 at 100 meters. Maximum frequency, 40 

 per cent between stations 5 and 6; all other records above 

 minimum (2 to 36 per cent), except between stations 6 and 

 7, where only 1 lorica was found. 



Temperature, ii?28-i4?32 (i2?8o); salinity, 35.51-36.06 

 (35.77); density, 26.91-27.15 (27.00); pH, 7.90-8.15 (8.10). 



Dictyocysta spinosa Kofoid and Campbell 

 Dictyocysta spinosa Kofoid and Campbell, 1929, p. 301, fig. 553. 



The rather stout lorica, with mitra-Yike fenestration and 

 distinct oral spines, has a length of 1.36 oral diameters. The 

 oral rim has 8 flattened arches; from the middle of each 

 arch arises an outspread needle-like spine. The collar is in- 

 verted subconical and flaring (8°); its length is 0.3 total 

 length. The diameter at the throat equals that of the rim, 

 and the sides are concave. There are 8 rounded, rectangular, 

 closed windows. The bowl is broadly ovate, has no shoul- 

 der, and reaches 1.24 oral diameters near its middle. The 

 aboral end is generally blunted. 



There are 8 rows of more or less irregular rows of uneven 

 fenestrae in the bowl. These increase in number but de- 

 crease in size toward the middle. 



Length, 42 to 46(1. 



Dictyocysta spinosa and D. extensa are the only species 

 with oral spines, and the latter species differs from spinosa 

 in the altogether different wall structure, having fewer large 

 fenestrae, and many small polygons on the longer, more 

 acute bowl. 



Recorded from four stations, two each in the Atlantic and 

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

 (23) in the Atlantic equatorial region, one (75) in the Gala- 

 pagos region, and one (135) in the California region. 



There are 1 pump sample and 3 net samples, all taken at 

 100 meters. Frequency, minimum. 



Temperature: Atlantic, net sample 22?42; Pacific, pump 

 sample i8?95, net sample i8?4o. Salinity: Atlantic, net 

 samples 34.88-37.05 (35.85); Pacific, pump sample 34.88, 

 net sample 35.47. Density: Atlantic, net sample 25.67; 

 Pacific, pump sample 24.96, net sample 25.55. pH ; Atlantic, 

 net samples 8.18-8.25 (8.21); Pacific, pump sample 8.34, net 

 sample 8.10. 



