20 SHALLOW-WATER FORAMINIFERA OF TORTUGAS REGION. 
Family LITUOLIDA. 
Genus AMMOBACULITES Cushman, 1910. 
Ammobaculites reophaciformis Cushman. 
(Plate 1, Figure 1.) 
Haplophragmium agglutinans H. B. Brady (part, not d'Orbigny), Rep. Voy. Challenger, 
Zoology, vol. 9, 1884, pl. 32, fig. 22 (not 19 to 21, 23 to 36). 
Ammobaculites reophaciformis Cushman, Proc. U. S. Nat. Mus., vol. 38, 1910, p. 440; Bull. 
104, U.S. Nat. Mus., pt. 2, 1920, p. 67, pl. 13, fig. 6; Proc. U. S. Nat. Mus., vol. 
59, 1921, p. 49. 
Test elongate, tapering, early portion consisting of a few chambers 
planospirally coiled and much compressed, making up but a small portion of 
the test, later and by far the larger part uncoiled, forming a straight linear 
series, circular in transverse section, and progressively increasing in size, the 
last-formed one being the largest; chambers fairly distinct; sutures slightly 
depressed; wall composed of angular fragments, smoothly finished; aperture 
pot oml terminal, simple, occasionally with a slight neck; color usually white 
or gra: 
Teiph of the Tortugas specimens hardly more than 1 mm. 
This species, which might be expected to be fairly common in 
this shallow-water coral-reef region, has been found to be surpris- 
ingly rare here. Single specimens were obtained at only 2 of the 
20 stations. This seems all the more noteworthy, as it occurs at a 
number of stations in the West Indies, and such conditions as prevail 
in the Tortugas region would seem to be ideal for its development. 
The specimen figured is very typical, showing the early coiled 
portion and the more or less pyriform chambers of the uncoiled 
part, gradually increasing in size toward the end. The only figure 
referred to above from the Challenger Report seems to represent 
this species, which should not be confused with Ammobaculites 
agglutinans (d’Orbigny). 
The species is known also from the Hawaiian Islands and westward 
across the Pacific, at least to the Philippine region. 
Genus TROCHAMMINA Parker and Jones, 1860. 
Trochammina advena, new species. 
(Plate 1, Figures 2 to 4.) 
Test small, composed of about 2.5 volutions, unequally biconvex, the 
dorsal side much more flattened than the ventral, the final whorl composed of 
4 chambers, more or less inflated; sutures slightly depressed; wall composed 
of sand-grains, apparently of quartz, with a considerable amount of light 
grayish cement; the surface rather smooth, whole test umbilicate below; the 
aperture at the inner margin of the final chamber short, rounded, with a 
very slight overhanging lip; color gray. 
Diameter up to 0.45 mm. 
The three stations from which specimens were obtained are all 
within the lagoon, and range from 4.75 to 10.5 fathoms. The 
bottom in all three stations is a fine white sand, mostly of calcareous 
