66 BULLETIN : MUSEUM OF COMPAEATIYE ZOOLOGY. 



width off the northern extremity of the island. Off the southwest face 

 of the ishand there is a shallow incipient lagoon. There is a large crack 

 running through the peak of the highest point of the island near the 

 southern point, as if the sea face might scale off at any moment and form 

 a vertical cliff. There is a fine vertical cliff along the northeast point of 

 the island over 100 feet in height, deeply undercut. From the lower 

 edge of this cliff numberless negro-heads extend over the surface of 

 the fringing reef flat, which is covered by lai'ge patches of.flourishing 

 corals. 



NORTH POINT OF MAEAMBO. 



Dana and Darwin both speak of fissures passing through the shore 

 shelf reef. The fissure we saw at Marambo I attribute to the giving 

 way of the shore bluffs from the undermining pi'eparatory to its shal- 

 ing off. 



Wangava. 



Plate 22. 



"Wangava. as seen from the passage between it and the northern ex- 

 tremity of Kambara, appears to be composed of two parallel ridges of 

 limestone, elevated to a height of nearly 300 feet. The island is steep to 

 on all sides, steep cliffs forming its eastern and westei'n faces. It is 

 suiTounded by a wide fringing i-eef (Plate 22) except off the north face, 

 where it becomes broken up into coral heads and patches. 



Vatu Leile. 



Plates 9, 17*, Figs. 1-4, and Plates 100-102. 



Yatu Leile, the westernmost island of the group we examined, is tri- 

 angular in shape, with a small lagoon extending along the eastern and 

 the northern fixces of the island (Plate 9). The lagoon is comparatively 

 shallow, not having anywhere a depth greater than five fathoms. Xearly 



