340 "ALIJATROSS" TROPICAL PACIFIC EXPEDITION. 



in continuation of the line of mangrove islands edging the reef flat 

 to the west of Port Lottin. The outer rim of mangrove islands extends 

 continuously from Point Lesson to Point Vauvilliers, where volcanic heads 

 crop out. On the northern extension of the reef flat coral boulders 

 form a gigantic spit, shutting off the inner lagoon from the wide reef 

 flat to the north (PI. 229). On this wide reef flat flanking the north- 

 west face of Kusaie (PI. 229) the islands of Hesi, Berard, and Gabert 

 rise to a slightly greater height than the numberless outcrops of volcanic 

 rocks which dotted, in all directions, the western barrier reef flat of 

 Kusaie from Point Vauvilliers to Coquille Harbor. As far as we could 

 see, the inner belt of mangroves which characterized the southwestern and 

 southern part of the west coast extends in a northerly direction, to join 

 the labyrinth of mangrove islands coming from the east, to the north 

 of Coquille Harbor. 



Pingelap. 



Plates 183, figs. 2-4 ; S25 ; 237, fig. 5. 



Pingelap,^ the next group we visited, is an irregularly rectangular atoll, 

 with sides of about two and one-half miles in length (PI. 227, fig. 5). 



Pingelap is undoubtedly an atoll built upon a volcanic platform, the 

 lagoon of which is enclosed on the east by Pingelap Island, and on the 

 northern horn by Tugulu and Takai Islands, two low islands well covered 

 with cocoanut trees. On the sea face the islands are flanked by heavy 

 shingle beaches (PI. 183, figs. 2-4); on the southernmost part of Pingelap 

 the lagoon face is flanked by a steep coral sand beach ; this gradually 

 passes into the wide reef flat which connects all the islands (PI. 227, 

 fig. 5). The reef flat encloses a shallow lagoon ; in the gap between 

 tlie two larger islands a shingle beach separates the lagoon from the 

 outer sea face. The western reef flat itself is even at low tide covered 

 with sufficient water to be navigable for canoes and small boats. It is 

 covered with large boulders and masses of smaller coral blocks. The 

 deepest part of the lagoon, said to be fifteen fathoms, seems to be in 



' A. Chart 772. 



