CARYN SEAMOUNT: A small conical peak, 1000 fathoms high, whose base is 8 miles in diameter, lies in the abyssal plain west of the Bermuda Rise (36° 45´N.). A magnetic survey of the peak has been published by Miller and Ewing (1956). They found an exceptionally large anomaly associated with the peak, which clearly showed its volcanic origin. Cores from the peak contained manganese nodules, altered volcanic rocks, and Upper Cretaceous to Recent fossils, which shows that it is at least as old as Upper Cretaceous. The base of the peak rises from the abyssal plain which extends out from the Hudson Submarine Delta. HORSESHOE SEAMOUNT GROUP: About 300 miles due west from the Straits of Gibraltar an impressive group of seamounts lies in a horseshoe-shaped arc. Several of these, most notably Ampere and Josephine seamounts, rise to less than 100 fathoms. Josephine Seamount is the largest of the group and lies along an east-west topographic trend (the Azores-Gibraltar Ridge). In the southern half of the Horseshoe Group the individual seamounts appear to be coalescing cones similar to the seamounts of the Kelvin Group. Seamounts of the northern half, although imperfectly known, seem to be elongated east-west. The southern half of the group appears to resemble volcanic cones, while in the northern half tectonic deformation seems to have played a larger part. The seamounts have been cored, dredged, and photographed by a Lamont Observatory expedition. The sediments obtained from the seamounts are middle Tertiary to Recent (Sutton _et al._, 1957). [Illustration: Heezen _et al._, PL. 16 FIGURE 1. WESTERN BERMUDA RISE FIGURE 2. CENTRAL BERMUDA RISE FIGURE 3. EAST-CENTRAL BERMUDA RISE FIGURE 4. EASTERN BERMUDA RISE REPRESENTATIVE PDR RECORDS FROM BERMUDA RISE Depth in fathoms.] [Illustration: Heezen _et al._, PL. 17 PDR RECORD, BERMUDA SCARP ZONE Depth in fathoms.] [Illustration: Heezen _et al._, PL. 18 FIGURE 1. HIGH FRACTURED PLATEAU FIGURE 2. UPPER STEP PDR RECORDS MID-ATLANTIC RIDGE Depth in fathoms.] [Illustration: Heezen _et al._, PL. 19 Area of each photograph is about 6 by 8 feet. PLATE 19.--OCEAN-BOTTOM PHOTOGRAPHS; MID-ATLANTIC RIDGE FIGURE 1. (Station T1-9, photo 42) Depth 1410 fathoms, location 48° 38´N., 28° 48´W., on Western Rift Mountains, Mid-Atlantic Ridge. In this plate Figures 1, 2, and 3 are closely spaced photographs less than 100 feet apart. Note the coarse-grained light and dark gravel in winnow row in the foreground and the light-colored clay or ooze bottom in background. Of the sixty photographs taken at this location three resembled Figures 2 and 3, several resembled Figure 1, and in the remainder the ocean floor was composed entirely of the light and dark gravel.