344 DISCOVERY REPORTS 



Genus Trochammina, Parker and Jones, 1859 



104. Trochammina squamata, Jones and Parker. 



Trochammina squamata, Jones and Parker, i860, RFM, p. 304, and table. 

 Trochammina squamata, Heron-Allen and Earland, 1913, CI, p. 50, pi. iii, figs. 7-10. 



Fourteen stations: 48, 51, 53; WS 71, 77, 87, 88, 89, 90, 91, 92, 93, 221, 248. 



Less widely distributed and less abundant than T. ochracea. The best specimens at 

 WS 87, 89, 92 and 93. Its distribution differs thus from that of T. ochracea. At most of 

 the other stations it is represented by few and relatively small individuals. There are 

 a good many specimens, notably at 53, which appear to be intermediate between 

 T. ochracea and T. squamata. Sessile at WS 92, 



105. Trochammina rotaliformis, J. Wright, MS. 



Trochammina inflata (Montagu) var., Balkwill and Wright, 1885, DIS, pi. xiii, figs. 11, 12. 



Trochammina rotaliformis, J. Wright, MS, Heron-Allen and Earland, 1913, CI, p. 52, pi. ii, 



figs. 11-13. 

 Four stations : 388 ; WS 83, 93, 408. 

 The specimens are small. 



106. Trochammina glabra, sp.n. (Plate VII, figs. 26-28). 

 Two stations: 388; WS 88. 



Test free, trochoid, spire somewhat elevated and dome-shaped, consisting of three 

 whorls gradually increasing in diameter, the outer containing eight chambers. All 

 chambers visible on the dorsal side, but the earlier series are often difficult to observe 

 owing to the extreme smoothness of the surface, the slightly curved sutural lines on this 

 side being thin and quite flush. On the ventral side the sutures are depressed and 

 straight and the chambers of the last convolution are quite distinct. They slope inwards 

 to a deeply sunk umbilicus. The aperture is large and loop-shaped on the inner edge of 

 the final chamber. Colour, brown of various shades. Constructed of very fine sandy 

 material with a large proportion of cement, the surface being very smooth and polished. 



Diameter up to 0-50 mm. Thickness 0-20 mm. 



This very handsome species was found in some numbers at 388 and WS 88, but not 

 elsewhere. Its nearest ally is T. rotaliformis, J. Wright, which it resembles in form, 

 differing principally in the number of chambers, which in Wright's species are only 

 4-5 in a whorl. 



107. Trochammina ochracea (Williamson). 



Rotalina ochracea, Williamson, 1858, RFGB, p. 55, pi. iv, fig. 112; pi. v, fig. 113. 

 Trochammina ochracea, Balkwill and Millett, 1884, FG, p. 25, pi. i, fig. 7. 



Twenty-three stations: 48, 53, 228, 230, 388; WS 71, 77, 79, 83, 84, 86, 87, 88, 89, 90, 91, 92, 93, 



108. 213, 221, 245, 408. 



Almost universally distributed. At southerly stations, WS 84, 87, 88, 89, the species 

 attains fine and typical dimensions. At nearly all the other stations it is represented by 

 comparatively small individuals. Sessile individuals were found at WS 77, 84, 87 and 

 88. The best specimens were at WS 88, where it was very common. 



