and we furthor concentrated ony effort thore in a section of reef near tho noerth end of the etoll which is roughly throa maics Jeng and cne mile wide, Thore are four dslands in this section of reel with a total avoa of about CO cquare miles, . Se ye wee . 4 ah + “wet In this beorad owan where wo have made collections end Ls ’ * . te observations, we *further limited we -% fas 4 onvseives for the princinal 2 rH Q is 9 to om u ey fe 3 § 0) he fae HY 3 ay o oO Q C3 mr c. fue % ay ° i 2 oO bet tet yp et mS pte I [40 fet o en Fe p 8 m somolblins: provran to radioactivity doterminatioens to onc island of about 15 ceres, and the width of the reef in this cntivre area runs botwwaca ene and one and a quarter isilos, Unfortunately, ZI cannot show you the photographs, but I “would like to diagram bricfly on the bhaekboard the broad sones this is a geod areca as far as proxinity to the tcost site, and also hore Wa have represented most of the magor lise zones that are found in the Atoll. This dis not vues for any given section ef reef in the Atoll, first of all, wa will start at the soa and at the roof, marsin on the seaward sics where we have tho grooved arona. I believe Dr, Odua, this afternoon, will show a photogravph. At this lip, we nave the so-cnalled Lithethambian Ridze. Tho R4ez0 is not too prominent in this arga, but it cofinitely is distinguishable as a very Slight risa. The Lithothanbian Ricco is made up of coral algne, coral lithium principally, and it is