FAMILY CERATOCORYACEAE 



41 



secondary thickenings running into the lists may devel- 

 op with age. There are scattered pores in the sulcal 

 area, as is shown in figure 53A. Ventral epithecal pore 

 usually not evident without dissection. 



Lists . Width of cingular lists 1.25 to 2.00 girdle 

 widths, somewhat greater ventrally than dorsally. 

 These lists may bear short delicate ribs in the middle 

 or, in heavily sculptured Individuals, may have strong 

 ribs running from the body to the edge of the lists. Gir- 

 dle transverse lists frequently very well developed (fig. 

 54C). Lists occur along all the sutures of body plates. 

 There is a heavy ridge running along the left edge of the 

 right accessory sulcal plate extending from the left pos- 

 terior corner of the fifth precinguJar plate to the flagel- 

 lar pore and along the right edge of the pore. 



Spines . Dorsal and ventral spines absent. Antapi- 

 cal spines three or four (figs. 53E, 54B, D). One list of 

 ventral antaplcal spine usually continuous with left sul- 

 cal list. The right antapical spine near but not at the 

 junction of po5, po6, and antl. Dorsally there are two, 

 rarely one, spines. When two, these spines are joined 

 by a list. These dorsal antapical spines are independ- 

 ent, i.e., they are not attached to the marginal lists of 

 the antapical plate as is the case with the other species 

 of the genus. At various curvatures of the body lists, 

 particularly at apex and antapex, there are apparent but 

 not real spines, especially in strongly sculptured indi- 

 viduals. 



Reproduction . Division is typical of the genus. 

 Both right and left daughter cells have been found. A 

 daughter cell with new right moiety is shown in apical 

 view in figure 53C. 



Variation . There is the usual variation in the thick- 

 ness of the walls and extent of surface sculpturing due 

 to age. Figure 54A, and B shows a specimen in which 

 the entire theca, including the intercalary zones, is 

 composed of thick, heavily ornamented walls. The two 

 dorsal antapical spines may be situated near the cor- 

 ners of the antapical plate or more or less close togeth- 

 er (fig. 54D); or they may be fused into one in the cen- 

 ter of the dorsal side of this plate (figs. 53E, 54E). The 

 girdle lists may be entirely without spines or they may 

 have short, thickening ribs running from the outer edge 

 or may have heavy ribs extending from the body. 



Historical . This species was first described by 

 Schutt (1895), 'who figured a form with two dorsal antap- 

 ical spines under the name Goniodoma acuminatum var. 

 armatum . Goniodoma fimbriatum Murray and Whitting 

 (1899) is identical with this species. The apical view 

 of Ceratocorys spinifera Murray and Whitting (pi. 30, 

 fig. 6c) probably also refers to this species. These au- 

 thors' apical view of a "mature specimen" (pi. 30, fig. 

 6d) may belong to this species. It is peculiar only in its 

 large size. It is 142 microns in diameter according to 

 the magnification given by these authors. The widest 

 specimen in the Carnegie collection is 93 microns, the 

 mean is 70 microns. Kofoid (1910, p. 182) described a 

 new species, C. magna , on the basis of this figure. It 

 does not seem desirable to retain this name among the 

 valid species, as there is always the possibility of a 

 mistake in magnification and there is no other feature 

 of this figure to distinguish it from C . 'armata . Kofoid 

 (1910, p. 181) was the first to bring C. armata under the 

 genus Ceratocorys, where it properly belongs. Linde- 

 mann (1925), however, was apparently unaware of Ko- 



foid's (1910) revision and lists it under the Schuttean 

 designation (p. 98, figs. 5, 6). He states that the plate 

 pattern is a little uncertain and questions the position of 

 the form in the genus Goniodoma . He even suggests a 

 relation to the genus Phalacroma. Matzenauer's C. ar - 

 mata (1933, fig. 22) must be considered questionable. 

 The hypotheca is too long for this species; only two 

 spines are Indicated; and, all together, the figure gives 

 the impression of representing an undeveloped speci- 

 men. 



Distribution . Ceratocorys armata is a widespread 

 tropical and subtropical species. It has been reported 

 from the Atlantic by SchOtt (1895), Murray and Whitting 

 (1899), Schmidt (1901), Pavillard (1931); from the Medi- 

 terranean by Schmidt (1901), SchrOder (1906), Kofoid 

 (1910), Pavillard (1916), Issel (1928), Lindemann (1925), 

 Schiller (1929), Forti (1922); from the Pacific by Schmidt 

 (1901), Lemmermann (1904), Kofoid (1910); and from the 

 Indian Ocean by Schmidt (1901), Schroder (1906). 



In the Carnegie collection this species was found at 

 79 stations: 11 in the Atlantic, and 68 in the Pacific. 

 There are 163 records of occurrence: 94 rare, 60 oc- 

 casional, and 9 common. It was found less frequently 

 with increasing depth. There are 87 records for the sur- 

 face, 41 for 50 meters, and 35 for 100 meters. There 

 are 117 net records and 46 pump records. The species 

 was found in both hemispheres and in all months but 

 June. The species was rather widespread at the tropical 

 and subtropical stations (fig. 52). In the Atlantic it did 

 not occur north of 40° north; and in the Pacific it oc- 

 curred between 35° north and 35° south latitude. 



The surface temperatures at the stations where the 

 species occurred at any depth varied from 19' to29°.4C. 

 The ranges of hydrographic conditions in situ were as 

 follows: temperature, 14°3 to 29°4 C; salinity, 30.0 to 

 36.8 o/oo; pH, 7.80 to 8.39; phosphate, 2 to 151 mg 

 P04/m3. 



Ceratocorys armata was found almost entirely with- 

 in the range of C. horrida, and its distribution is prob- 

 ably limited by the same factors that limit the latter 

 species. It is a much rarer form than C. horrida , so 

 that its records of occurrence are not so continuous. 

 This does not necessarily mean, however, that its oc- 

 currence is sporadic. Its occurrence outside the range 

 of C. horrida was in the southeastern Pacific betwe.en 

 Easter Island and South America at stations 62, 63, and 

 64a, where the surface temperatures were between 19° 

 and 20°. This exception probably was due to a local in- 

 oculation of this general region similar to that of C. hor - 

 rida at station 61a. 



The data indicate that C. armata Is more limited to 

 the warm water than is C. horrida . The species is not 

 found regularly enough within its range, however, to al- 

 low us to consider as really significant the negative rec- 

 ords along the limits of the distributional area. It oc- 

 curred in the North Atlantic Drift as far to the north as 

 did C . horrida , viz., to station 2, where the temperature 

 was 20°5. Beyond the California Current it did not ap- 

 pear until a surface temperature of 22°9 was attained; 

 off Japaniit did not occur where the temperature of the 

 surface water was less than 23° 9; and south of Easter 

 Island it was found as far south as station 57, where the 

 surface temperature was 19°0. It is not sufficiently 

 common to be of great value as an indicator of tropical 

 water; its presence is significant but not its absence. 



