88 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 
the north at Phosphate Hill, which exceeds 900 feet in height, while the 
highest ground in the island occurs at Murray Hill on the west, where 
the altitude reaches 1170 feet. During the period of elevation of the 
central nucleus there were several pauses, as a result of which fringing 
reefs occur at various levels. These are now represented by a series of 
four slopes, or inland cliffs, continuous nearly all round the island. 
1. The newest or present fringing reef. 
2. The shore terrace, 50 feet in height. 
3. The first inland cliff, from 80-300 feet in height. 
4. The second inland cliff, ranging from 320-600 feet in height. 
Egeria Point Scale of Miles. 
ODL UpE anisms 
CuristmMas ISLAND. 
Faulting and slipping have occurred fairly extensively, especially on 
the rim of the island, and it is largely owing to this cause that the ter- 
races are not quite continuous. This is particularly the case on the north- 
west at Flying Fish Cove, where a fairly complete section is seen from 
the older Eocene and Oligocene limestones at the base up to the Miocene 
rocks at the top of the cliff. Specimens have been examined which il- 
lustrate sections both from the older rocks and also from the older and 
newer inland cliffs or fringing reefs. The results of the examination of 
these rocks will now be given in the order mentioned. 
Older Rocks (Eocene to Miocene). 
Fryine Fish Cove. Chemical. — At this part of the islarid a good 
section occurs in the sea cliff. Rocks of Eocene or Oligocene age are 
exposed at the sea level, while on the plateau above, corals occur to 
