no "TERRA NOVA" EXPEDITION. 



megalosplieric aucl niicrospheric forms occur. The test is constructed of coarser 

 sand-grains than are usually employed by the genus, but its chief distinction lies 

 in the fairly uniform diameter of the tube and its roughly circular outline, as 

 contrasted with the compressed section of A. tenuis. 



157. Ammodiscus yordialis (Jones and Parker). 



Trochammina squamata (jordialis, Jone.s and Parker, 1860, RFM. p. 304. 



Ammodiscus gordialis, Herou-Allen and Earland, 19U. etc., FKA. 1915, p. 618, pi. xlvi, fig. 26. 



Stations 2, 4, 6, 18, 22, 26. 27, 29, 38. 40. 45-48, 50, 54, 55 (+ K. I., D.). 



More generally distributed in the Antarctic than in the N.Z. area. The best 

 N.Z. Station was Station 6, where it occurs both free and attached. The best 

 Antarctic Station was No. 26, where it is very common, large, free and 

 attached. Sessile individuals were observed at Station 46 (growing on a living 

 Pycnogonid), and at Station 55. At Stations 18 and 22 (single specimens) the test 

 was smoothly constructed with a maximum of cement, an unusual characteristic 

 in this species. At Station 29 a specimen occurred presenting all the charac- 

 teristics of Doderlein's Psammonyx vulcanicus (Doderlein, 1892. Verh. Deutsch. 

 geol. Ges. p. 145. See R. 1903, ZRR. p. 279, fig. 127 a, b), but the size is that 

 of the normal A. cjordialis, and does not reach the gigantic proportions recorded 

 by Rhumbler from Japan. 



158. Ammodiscus charoules (Jones and Parker). 



Trochammina squamata charoides, Jones and Parker, 1860, RFM. jo. 304. 

 Ammodiscus charoides, Heron-Allen and Earland, 1914, etc., FKA. 1915, p. 618. 



Stations 16, 18, 20-23, 27-29, 32, 35, 36, 40, 42 (-f T. d. F.). 



Exclusively confined to the Antarctic, and almost exclusively to the deepest 

 water Stations. The best development at Station 22. Occasional large and well- 

 developed specimens at other Stations, but on the average the individuals are 

 much smaller than usual. This is particularly noticeable at Station 40, where the 

 species was very common, and to a less extent at Station 29. 



[Porcellanous isomorph Cornuspira charoides, H.-A. & E. 1914, etc., FKA. 

 1915, p. 593, pi. xlvi, fig. 15.] 



159. Ammodiscus shoneanus (Siddall). Plate I, fig. 22. 



Trochammina shoneana, Siddall, 1878, FRD. j). 46, figs. 1, 2. 

 Ammodiscus megaspira, Berthelin, 1878, FBP. p. 223 (p. 23 in reprint). 

 Turritella shoneana, Cusliman, 1910, etc., FNP. 1910, p. 79, fig.s. 107-109. 



Stations 2, 26, 27, 29, 38, 40, 48, 55. 



A single specimen, typical, from the N.Z. area. The Antarctic records are few 

 in number and the specimens rare, but they are, generally speaking, exception- 

 ally well developed, particularly at Station 48. The Antarctic specimens are 



