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there are two main advantages of studying asymptotic giant branch ( agb ) stars in the galaxies of the local group ( lg ) .
first that we are able using the current instrumentation to resolve their stellar content and second that these stars can be considered to be approximately all at the same distance .
recent studies of agb stars in the magellanic clouds allowed us to gain insight into the near  infrared ( near  ir ) stellar content of the galaxies , their surface distribution and the ratio between carbon  rich ( c  rich ) and oxygen  rich ( o  rich , m  type )
agb stars easily statistically distinguished in the colour  magnitude diagram ( cmd , @xmath0 , @xmath1 ) .
more recent near  ir observations of other galaxies in the local group have been analyzed to tell us similar informations .
among the latest near  ir instruments denis and 2mass have released a large amount of data on agb stars in the magellanic clouds . in particular in the denis catalogue towards the magellanic clouds ( dcmc  cioni et al .
2000a ) there are @xmath2 agb stars in the large magellanic cloud ( lmc ) and @xmath3 in the small magellanic cloud ( smc ) , of which @xmath4 and @xmath5 are c  rich .
blanco et al . ( 1983 ) estimated about @xmath6 and @xmath7 c  rich stars in the lmc and smc , respectively . accounting for about @xmath8 misclassification among the m01 stars below the tip of the red giant branch ( trgb ) which are missed by our selection criteria based on the near  ir colour  magnitude diagram ( cmd ) , we detect most of the agb stars in both galaxies .
infact we detect about the same c stars found by kontizas et al .
( 2001 ) in the lmc ( @xmath9 ) and those @xmath10 found by rebeirot et al .
( 1983 ) in the smc .
agb stars are easily distinguished in the cmd ( @xmath11 , @xmath12 ) as the plume of objects above the trgb redder of a given line that discriminates between the younger and older populations ( cioni et al .
these agb stars distribute smoothly over the surface of the clouds in contrast with the bar  like and patchy distribution of the younger stars . in the cmd ( @xmath0 , @xmath1 ) c  rich agb stars occupy a red branch compared to the location of o  rich stars .
the distribution of the ratio between c  rich and o  rich ( c / m ratio ) agb stars outlines in the lmc a ring  like structure of increasing values ( cioni & habing 2003 ) . because the c / m ratio is a strong indicator of metallicity the first global evidence that there is a radial metallicity gradient in the lmc
was found .
the ratio is patchy and irregularly distributed in the smc . by fitting the distribution of points ( log(@xmath13 ) versus [ fe / h ] ) in other galaxies of the lg a metallicity spread of about @xmath14 dex within each cloud
was derived .
the larger uncertainty remains in the calibration and scatter of this relation .
based on the results obtained in the magellanic clouds i started in collaboration with habing a near  infrared campaign from the la palma observatory to mosaic other galaxies of the lg in @xmath12 , @xmath15 and @xmath1 .
the goal is to find , study and compare the agb stellar population .
fig.1 shows : the ( @xmath0 , @xmath1 ) diagram for all the sources detected within an area of @xmath16 centered on ngc6822 ( a ) , the histogram of the @xmath0 colour at about @xmath17 mag above the trgb where the dashed line discriminates between o  rich and c  rich agb stars ( b ) , and the histograms of @xmath15 ( c ) and @xmath1 ( d ) where the dashed line indicates the approximate location of the trgb . in ngc6822 we detect about @xmath18 c stars , approximately @xmath19 more than letarte et al .
( 2002 ) , and @xmath20 m stars .
the distribution of the whole agb population is shown in fig.2 while fig.3 shows the distribution of the c / m ratio . using the same relation discussed in sect.2
we derive that the gray scale and the contours span a range of 1.65 dex in [ fe / h ] .
contrary to nowotny et al .
( 2003 ) we do detect regions with a different c / m ratio .
note that in the @xmath1 band the differential reddening is negligible and that foreground stars have been removed .
the striking difference between the two figures indicates the potential of the c / m ratio to study the chemical history of galaxies .
similar figures , though with less statistics have been obtained for ngc147 and ngc185 .
observations of draco have just been reduced and unfortunately the observations of leoa , leoi and leoii took place during variable sky conditions which considerably affect the quality of the resulting cmds .    in the southern hemisphere the central region of a few galaxies has been observed using sofi at the ntt in the near  ir wave bands by tolstoy back in 1998 .
the cmds of ddo210 , fornax , sagdig and pegasus show clear red giant branches reaching in fornax the red clump .
these galaxies are not rich in agb stars especially of c type except pegasus that shows a plum of objects with quite red @xmath0 colours .
these relatively deep data are probably suitable to derive the metallicity and the age of the observed region ( about @xmath21 ) from the slope and colour of the rgb as in davidge ( 2003 )
. new observations of these and other galaxies visible from the southern hemisphere took place at the end of july 2003 in collaboration also with reijkuba .
the wealth of near  ir data on galaxies in the local group either than the magellanic clouds will definitely benefit from the latest theoretical results by marigo et al .
the authors were able to successfully model the red tail of c stars producing a synthetic ( @xmath1 , @xmath0 ) diagram in very good agreement with the observational data .
the key ingredient is to assume an opacity that in cool stars varies with the chemical composition in addition to the assumption of a given pulsation mode ( the first overtone for c stars ) .
large scale informations on agb stars in the magellanic clouds , ngc6822 , ngc147 and ngc185 have been discussed : their location in the near  ir cmd , their spatial distribution and that of the c / m ratio .
the latter is an important abundance indicator , especially for those systems too far away to measure abundances with other tracers . in the near future
we will complete the reduction of complementary i  band measurements , try to complete the observations of some targets not yet fully mosaiced and to continue a monitoring program ( in the i  band ) that will provide us with an indication about the variability of the target stars .
ultimately we count on publishing homogeneous catalogues of agb variables that will be useful to the whole community to perform stellar population studies in these relatively nearby galaxies .
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results obtained in the magellanic clouds using the latest near  ir denis survey are briefly revised . 
 this sets the base to a similar study of agb stars in other galaxies in the local group and in particular in ngc6822 .    
 # 1_#1 _ # 1_#1 _ =    # 1 1.25 in .125 in .25 in