1 
C. R. 
19 
Collection Humber 
Portulaca lutea S ol.- growing near the ruins of the 
Willed pit SiT of the compsite - associated with Lepturus 
and Boerhaavia . Live collection. 
Algae - a general collection from surge channels on the 
south reef - appear to be + 10 genera present covering 
the exposed rocks and sides of tidal pools. 
21 October 19w - McKean Island - Wind constant in both morning and afternoon 
hours. The cloud cover seems to pick up late in the afternoon or early evening, 
and, showers are ouch more likely at night. The south reef was observed to be 
the most abrupt 0® the island. This is especially noticable as the tide moves 
in and up the surge channels. The abruptness of the reef is further indicated 
by the distance to which the algae grow up the reef • these being only + 20 feet 
(maximum) of bare rock (or poorly covered rock) at low tide. On all other sides 
of the island the reef is much wider, and, consequently there is a wider sterile 
bond below the beach. 
McKean Island has a unique shape among the islands of the Phoenix group: 
nearly circular as though the coral growth had formed a ring around the top, 
almost perfectly round cone of a submerged volcanic mountain. Despite storm 
action and weathering this island may retain or reflect the geological structure 
from *&ich it arose. (F. Sibley discounts this theorgy but offers no alternative). 
I believe there are some islands in the maldlve group which have been built 
in this fashion. 
At the southwest end of the island is the trunk of a buttressed tree 
(probably not Pisonia ) washed about 30 feet inland from the beach. The trunk 
is + 32 feet long. 1 think that this was deposited by wave action. Also on 
the southwest side are several large coral boulders at the surface. These 
resemble several coral bouldres which appear on the reef at low tide. I do 
not mink we can underestimate the effect of the sea forces on the topography 
m well as the living things of the island. 
At 6 P.M., October 21, 1964-, the lagoon on McKean Island was observed to be 
about 90 percent covered with seepage water from the high tides. In the mid 
north central area on the largest dry "Island" are + 350 Blue-faced Boobies 
one of the largest elubs I have seen. 
