260 "ALBATROSS" TROPICAL PACIFIC EXPEDITION. 



Where the shingle is low the water passes at half or high tide directly 

 into the lagoon, while in other parts of the eastern horn of this atoll, water 

 can only enter the lagoon at high stages of the tide, and in some parts 

 where the beach is highest, it flows around the two ends of the shingle. On 

 the south face of Taritari the land rim is flanked by a series of steep sand 

 beaches, alternating with beach rock conglomerate ledges and coral shingle 

 beaches from four to six feet in height (PI. 155, fig. 1). Large blocks of 

 beach rock or of conglomerate are often mixed with the shingle. 



The larger forest trees characteristic of the South Pacific atolls grow 

 close to the highest ]xiinb of the beach ; there are neither Pisonias nor the 

 scrub vegetation usually met with on the summit of the outer beaches 

 (PL 155). 



Judging from the position of the line of the brea,kers, the outer reef flat 

 is extremely narrow. In the gap between the two principal islands of the 

 southern face (PI. 224, fig. 4) we found a series of islands and islets on the 

 inner face of the broad reef flat forming spits extending at right angles to 

 the outer edge of the reef platform (Pis. 152, fig. 2 ; 153 ; 156, fig. 1 ; 157), 

 which at this point is marked by a low, steep, coarse, coral rock shingle 

 beach. The islands and outer islets are flanked on their sea faces by beach 

 rock or conglomerate shingle, while on their lagoon face the spits are com- 

 posed of fine coral sand. This peculiar combination of islands and of low 

 outer beaches with two inner rows of islands forming a secondary lagoon 

 we have described in Tarawa and elsewhere (Pis. 152, fig. 2 ; 153 ; 156, 

 fig. 1 ; 157). 



At a point near the middle of the south shore we obtained an excellent 

 view across the outer rim, towards the interior of the lagoon, with the 

 islands and islets beginning to build np secondary lagoons (Pis. 152, 153), 

 the outer edge of the reef flat being edged with a high dam of black coral 

 rock shingle (PI. 158). This dam extends fully a mile to one and a half 

 miles from the gap. 



West of the gap on the south face, the shore of the rim of Taritari 

 consists of alternate sand and shingle beaches (Pis. 152, figs. 3, 4; 155, 

 fig. 1), or reaches of beach rock or conglomerate, and flat-topped ledges. 



Here and there on the south shore of Taritari we find a still different 



