ii6 DISCOVERY REPORTS 



Generally distributed all over the area and at all depths, but except at Sts. 177 

 (1080 m.) and WS 203 (4259 m.), where it is common, and at St. WS 471 (3762 m.), 

 where it is frequent, the species is usually rare and often represented by single speci- 

 mens. The best and largest specimens were observed at St. WS 507 B (580 m.); very 

 typical but smaller specimens at Sts. 363 and WS 474. 



231. Textularia nitens, Earland (SG 157). 



Thirty-one stations : 169, 171, 177, 180, 190, 192, 194, 196, 197, 199, 209, 366, 369; Port Lockroy; 

 62° 57' S, 60° 20' 30" W; WS 377, 384-6, 395, 480, 484, 489, 494 A, 497, 506, 507 A, 507 B, 509, 515, 

 516. 



Very good specimens were frequent in the anchor mud at Port Lockroy, also at St. 

 WS 509 in 445 m. At the remaining stations, which are widely scattered, the species is 

 rare or very rare. Moderate depths appear to be most favoured, the majority of the 

 records being under 1000 m., and the deepest 2514 m. at St. 169. The species is very 

 similar to T. {Pseudobolivina) antarctica (No. 232), but is distinguishable by its smaller 

 size, its more compressed chambers, and its normally arched textularian aperture. 



The species has recently been recorded from 280 fathoms in the Bay of Whales, Ross 

 Sea (W. 1934, FRS, p. 2). 



232. Textularia antarctica (Wiesner) (Plate IV, figs. 39-43). 



Bolivina punctata var. arenacea, Heron-Allen and Earland, 1922, TN, p. 133, pi. iv, figs. 21, 22. 

 Pseudobolivina antarctica, Wiesner, 193 1, FDSE, p. 99, pi. xxi, figs. 257, 258, pi. xxiii, Stereo- 

 fig. C. 



Twenty-four stations: 169, 171, 177, 181, 192, 195, 198, 369; 62" 57' S, 60° 20' 30" W; WS 377, 

 383, 479, 480, 482, 483, 494A, 496, 506, 507B, 509, 510, 512, 514, 515. 



Frequent at St. WS 509 in 445 m., rare or very rare elsewhere, but many excellent 

 specimens were found, especially at Sts. 169, 177, WS 494A. The depths range down to 

 2552 m. at St. WS377, but it seems most at home at depths under 1 000 m. Specimens with 

 a twist in the long axis were noted at Sts. 198 and WS 480, very similar to those figured 

 in the Terra Nova report. Both megalospheric and microspheric forms were observed. 



The species was originally described and figured from the Antarctic (Ross Sea), in 

 the Terra Nova report, and, with some allied forms, was regarded as an arenaceous iso- 

 morph of the hyaline genus Bolivina. I think that discoveries made since the date of 

 that report have rendered the theory of isomorphism in the Foraminifera untenable ; 

 there are too many instances of similar structural design in genera which have no pos- 

 sible relation to each other. Perhaps no stronger argument against the theory could be 

 found than in Miliammina, where the adult shell resembles various species of Miliolina 

 almost exactly, but the early stages of development {fide Cushman) are not milioline. 



Wiesner has created a new sub-family Pseudobolivininae and the new genus Pseudo- 

 bolivina (W. 1 93 1, FDSE, pp. 98-99) for the reception of the Terra Nova forms, but it 

 seems to me to be superfluous. Failing the theory of isomorphism, the genus Textularia 

 appears to be sufficient for their reception. They are all normal Textidariae in every 

 respect except the sht-like aperture, which is at right angles to the normal direction. 

 But the variety of apertures already observed and admitted in the genus Textularia is 

 more than sufficient to cover this further abnormahty. 



