This pa per, extensio n of a n earlier work [Ba nd yo pad hyay a nd Nl o n tes, 1963 ], exa mines ce r ta in feat ures of t he c-a nd t he h-type of s poradi c E fro m t he data of so me So u t h American station s Il ear t he magnetic equ ator. The features exam in ed in clu de diurn a l, seasona l, a nd lun ar var iatio n of occurren ces an d co rrelations wi th geo magnetic d ist urb ances. The op.c urrences of bot h Es-c a nd Es-h a r c fo und to co rrelate wit h m agnet ic d ip, bein g

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... infrequ ent ncar t he mag netic eq uato r. The paper a lso examines t he res ults o f an equ ato ria l VH F for ward scatter ex perim en t a nd co m par es t hem wit h cer ta in featu res of Es-q noted before fr o m H ua n cayo io nogr a m s a nd rl'po r ted in t he earlier wo rk . The close ag reem en t obser ved su ggrsts t h~Lt t he irreg ula rit ies of ioni zatioll which ma nifest t hemselves in t he t wo diffr rr n t kin ds of obsl'r vatio ns a re either t he same o r h,wr f( corn m on o ri g in . . . . . M ats us hi ta, S. (1952), Semidiurn allunar Val'latlon III spo ra d IC E, J . Geomag. Geoelect. 4, 39-40. Mats ushi ta, S. (1953), Lun ar tidal vari ations in t hcsporadic E r egion, R ep t . I onos pheric R es. ! apan 7, 45-52 . . M ats us hi ta, S. (1957), Lun ar efl ects on t he eq uaton a l E s, J . At mosp llCri e Terr est. P hys. 10, 163-165. (P aper 68 D 11-42 7)