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                                                                    EXHIBIT 21.1


         MCN ENERGY GROUP INC.: MCN Energy Group Inc. (MCN or the Corporation)
is a diversified energy holding company with markets and investments throughout
North America and in Asia. MCN is organized under the laws of the state of
Michigan and has its principal executive offices at 500 Griswold Street,
Detroit, Michigan 48226. The Corporation owns directly all of the outstanding
common stock of Michigan Consolidated Gas Company (MichCon), Citizens Gas Fuel
Company (Citizens), and MCN Investment Corporation (MCNIC). MCN's major business
groups are Gas Distribution and Diversified Energy. Except where otherwise
indicated, the companies set forth below are Michigan corporations located at
500 Griswold Street, Detroit, Michigan 48226.


                                GAS DISTRIBUTION

         MCN, through the following subsidiaries, operates the largest natural
gas distribution and intrastate transmission system in Michigan and one of the
largest in the United States.

A.       MICHIGAN CONSOLIDATED GAS COMPANY (MichCon): MichCon is a public 
         utility engaged in the distribution and transmission of natural gas 
         in the state of Michigan.  MichCon was organized in 1898 and, with 
         its predecessors, has been in business for nearly 150 years.  MichCon 
         serves 1.2 million residential, commercial and industrial customers 
         in the Detroit, Grand Rapids, Ann Arbor, Traverse City and Muskegon 
         metropolitan areas and in various other communities throughout the 
         state of Michigan.  MichCon conducts substantially all of its 
         business in the state of Michigan and is subject to the jurisdiction 
         of the Michigan Public Service Commission (MPSC) as to various phases 
         of its operations, including gas sales rates, service, and accounting.
         Except where otherwise indicated, the companies set forth below are 
         wholly owned subsidiaries of MichCon.
 
         1. Michigan Consolidated Homes Limited Dividend Housing Corporation 
            a/k/a MichCon Homes, a Delaware corporation, was sold on 
            April 1, 1997. MichCon Homes operated a 130-unit, low and moderate 
            income housing project in Detroit, Michigan.

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      2. MichCon Development Corporation, through its various partnership
         arrangements, is engaged in the design, construction and management of
         Harbortown, a residential and small commercial development constructed
         on a 39 acre parcel along the Detroit River in Detroit, Michigan.
 
      3. Blue Lake Holdings, Inc. (Blue Lake), holds a 25% interest in Blue Lake
         Gas Storage Company, a partnership that has converted a depleted
         natural gas field in northern Michigan into a 46 Bcf natural gas
         storage field which it now operates.

      4. MichCon Fuel Services Company markets natural gas as a vehicular fuel
         and markets energy to residential and commercial customers through a
         transportation brokerage pilot program.

      5. MichCon Pipeline Company, through the subsidiaries below, is engaged in
         pipeline projects.

         a.  MichCon Gathering Company owns and operates the Antrim Expansion
             Pipeline.

         b.  Saginaw Bay Pipeline Company is the 66% general partner in Saginaw
             Bay Area Limited Partnership, a partnership that operates a
             126-mile pipeline which transports natural gas and natural gas
             liquids from reserves in east-central Michigan to natural gas
             processing plants in northern Michigan.

         c.  Saginaw Bay Lateral Company is the 46% general partner in a
             partnership which owns and operates lateral pipelines
             interconnecting with the 126-mile pipeline previously described.

         d.  Westside Pipeline Company invests in various pipeline assets in
             Michigan.

         e.  Thunder Bay Gathering Company acquired the Thunder Bay Pipeline in
             December 1997. Thunder Bay Pipeline consists of 44 miles of
             gathering lines situated in Alpena and Alcona Counties in northeast
             Michigan.

         f.  MichCon Lateral Company was formed in 1997 to own, operate and
             construct natural gas pipelines.

      6. Huron Pipeline Company was formed in 1996 to acquire an ownership
         interest in the ANR Link Pipeline, which transports natural gas to
         Canada through a pipeline owned by Niagara Gas Transmission Limited, a
         subsidiary of The Consumers Gas Co. Ltd.

         a.  Huron Gas Services Company, formed in 1996, markets pipeline 
             transportation services.
 
      7. Kalkaska Gas Storage Limited Partnership holds a 53.5% general
         partnership interest in the Cold Springs Gas Storage Limited
         Partnership in Kalkaska County, Michigan.

B.    CITIZENS GAS FUEL COMPANY: Citizens is a public utility engaged in the
      distribution and transmission of natural gas. Citizens was organized in
      1951 and, with its predecessors, has been in business for more than 140
      years. Citizens serves approximately 14,000 residential, commercial and
      industrial customers in and around Adrian, Michigan. Citizens'
      principal executive offices are located at 127 N. Main Street, Adrian,
      Michigan 49221. Citizens conducts all of its business in the state of
      Michigan and its rates are set by the Adrian Gas Rate Commission. Other
      various phases of its operations are subject to the jurisdiction of the
      MPSC.




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C.       SOUTHERN MISSOURI GAS COMPANY: MCN has a 47.5% interest in Southern
         Missouri Gas Company, L.P. which is a public utility engaged in the
         distribution and transmission of natural gas. SMGC was organized in
         1996 and, with its predecessors, has been in business since 1995. SMGC
         serves approximately 6,000 residential, commercial, and industrial
         customers in Southern Missouri. The principal executive offices of SMGC
         are located at 301 East 17th Street, Mountain Grove, Missouri 65711.
         SMGC conducts all of its business in the state of Missouri. Its rates
         and other various phases of its operations are subject to the
         jurisdiction of the Missouri Public Service Commission.


                               DIVERSIFIED ENERGY

D.       MCN INVESTMENT CORPORATION (MCNIC): Organized in 1986, MCNIC is the
         holding company for MCN's various diversified energy subsidiaries.
         MCNIC, through its subsidiaries and joint ventures, engages in gas and
         oil exploration, development and production, provides gathering,
         processing and transmission services, engages in non-regulated energy
         marketing activities, invests in electric generation and distribution
         facilities, provides gas storage services and is involved in other
         energy-related businesses. Except where otherwise indicated, the
         companies set forth below are wholly owned subsidiaries of MCNIC.
 
 
         Exploration & Production

                    1.   MCNIC Oil & Gas Company (MOG) is engaged in natural gas
                         and oil exploration, development and production in the
                         Midwest/Appalachia, Midcontinent/Gulf Coast and Western
                         regions of the U.S. The following companies are direct
                         subsidiaries of MOG:
                              
                         a.       Elmira Antrim Company
                         b.       GeoTrend Exploration, Inc.
                         c.       Green Oak Development Company
                         d.       Green River Antrim Company
                         e.       Otsego Exploration Company, L.L.C.
                         f.       MCNIC Enhanced Production, Inc. has a 75% 
                                  interest in Otsego EOR, L.L.C.
                         g.       MCNIC Oil & Gas Midcontinent, Inc.
                         h.       MCNIC Oil & Gas Canada, Inc. (a New Brunswick 
                                  corporation)
                         i.       MCNIC Oil & Gas Properties, Inc.
                                  i.    SEM, a 50% joint venture, was
                                        established to buy and sell E & P 
                                        Properties
                         j.       MCNIC Oil & Gas Reid Properties, Inc. (a 
                                  Delaware corporation)
                                  i.    Appalachian Methane, Inc., a Delaware 
                                        corporation, holds a 50% interest
                                        in Buchanan Production Co., a Virginia 
                                        general partnership.
                                  ii.   Appalachian Operators, Inc., a Delaware 
                                        corporation, holds a 50% interest
                                        in Buchanan Production Co., a Virginia 
                                        general partnership.
                                  iii.  MCNIC Oakwood Gathering, Inc. (a 
                                        Delaware corporation)
                         k.       MCNIC West Coast Company
                         l.       Warner Antrim Company
                         m.       MCNIC Oil & Gas CV Company
                         n.       Pageant Corporation

         Pipelines & Processing

              MCNIC's Pipelines & Processing businesses are involved in 
         ventures that gather and transport natural gas from producing fields
         to processing plants and/or markets. This business also includes
         plants which process natural gas to remove CO2 and other impurities
         and recover natural gas liquids. Additionally this segment has an
         investment in a methanol production facility and other 
         energy-related businesses.
 

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         2.       MCNIC Pipeline & Processing Company engages in 
                  pipeline and processing projects through the following 
                  subsidiaries and partnerships.
 
                  a.    MCNIC Offshore Pipeline & Processing Company holds a 33%
                        interest in the Blue Dolphin System.
                  b.    MCNIC Michigan Holdings, Inc.
                        i.    MCNIC CSG Pipeline Company holds a 50% interest 
                              in Cardinal States Gathering.
                        ii.   Bagley Processing Company (47% partnership 
                              interest)
                        iii.  Warner Treating Limited Liability Company (95% 
                              interest)
                        iv.   Terra-Westside Processing Company (85% interest)
                        v.    ThunderBay Pipeline Company, L.L.C. (90% interest)
                              holds 2 CO2  Processing Plants.
                  c.    MCNIC East Coast Pipeline Company holds a 20% interest
                        in the proposed Portland Natural Gas Transmission
                        System.
                  d.    MCNIC Jonah Pipeline Company holds a 33% partnership
                        interest in Jonah Gas Gathering Company.
                  e.    MCNIC Gulf Coast Gathering Company, holds a 1% general
                        partnership interest in Copano Pipeline & Processing 
                        Group, L.P.
                  f.    MCNIC Gulf Coast Limited, Inc., holds a 49% limited
                        partnership interest in Copano Pipeline & Processing 
                        Group, L.P., and a 90% limited partnership interest in
                        CFS/Upper Gulf Coast, L.P., Copano Pipelines/Upper 
                        Gulf Coast, L.P., and CES/Upper Gulf Coast, L.P.
                  g.    MCNIC Mobile Bay Pipeline Company holds a 34.6% interest
                        in Dauphin Island Gathering Partners.
                  h.    MCNIC Mobile Bay Processing Company holds a 42.8%
                        interest in Mobile Bay Processing Partners.
                  i.    MCNIC South Texas Gathering Company holds a 1% general
                        partnership interest in each of CFS/Copano Bay, L.P.,
                        CFS/South Texas, L.P., CFS/Agua Dulce, L.P., CFS/Upper
                        Gulf Coast, L.P. and CES/Upper Gulf Coast, L.P.
                  j.    MCNIC Upper Gulf Coast Pipeline & Processing Company
                        holds a 1% interest in Copano Pipeline/Upper Gulf Coast,
                        L.P.
                  k.    MCNIC General Methanol Company holds a 1% general
                        partnership interest in Lyondell Methanol Company, L.P.
                  l.    MCNIC Methanol Holdings Company holds a 24% limited
                        partnership interest in Lyondell Methanol Company, L.P.
                  m.    American Central Western Oklahoma Gas Company (40%
                        interest)
                  n.    Crown Asphalt Ridge, L.L.C. (75% interest)
                  o.    Indiana Gathering, L.L.C. (69.5% interest)
                  p.    MCNIC East Texas Gathering Company holds a
                        39.9% limited partnership interest in American Central
                        Eastern Texas Gas Company, L.P.
                  q.    MCNIC East Texas Pipeline & Processing Company holds 
                        a 0.1% general partnership interest in American Central 
                        Eastern Texas Gas Company, L.P.
                  r.    MCNIC CO2 Investment Company holds a 41.5% limited 
                        partnership interest in PSCO2, L.P., a CO2 pipeline 
                        project.
                  s.    MCNIC Permian Basin Company holds a 0.99% general 
                        partnership interest in PSCO2, L.P.
                  t.    MCNIC Rodeo Gathering Inc.




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Energy Marketing, Gas Storage & Electric Power

        MCNIC's Energy Marketing, Gas Storage & Electric Power businesses pursue
opportunities throughout North America and Asia, including energy marketing to
large-volume customers, investing in electric generation and distribution
facilities and providing gas storage services to affiliated marketing companies,
other gas utilities, pipeline companies and large-volume gas users.
 
        3.   CoEnergy Trading Company is engaged in the purchase and sale of
             natural gas to large-volume gas users and gas and electric
             utilities in Michigan, the Midwest, the eastern United States and
             Canada. CoEnergy Trading Company holds a 50% interest in the
             following:
 
             a. U.S. CoEnergy Services, a Wisconsin general partnership
             b. Torch CoEnergy, L.L.C.
             c. DTE-CoEnergy, L.L.C.

        4.   CoEnergy Canadian Holdings, Ltd., a New Brunswick corporation, was
             formed to market and sell natural gas in Canada and the
             northeastern United States.
 
        5.   CoEnergy Supply Company engages in the purchase and sale of natural
             gas, a portion of which is produced by subsidiaries of MCNIC Oil &
             Gas Company.

        6.   MCNIC Gas Storage Company

             a. South Romeo Gas Storage Company, a Michigan partnership in which
                MCNIC Gas Storage Company has a 50% interest, owns and operates
                the Washington 28 Gas Storage Field, a 10 Bcf storage field in
                southeastern Michigan which provides storage services to MCNIC's
                Energy Marketing and Electric Power operations. South Romeo Gas
                Storage Company holds a 33% interest in South Romeo Gas Storage
                Corporation.

             b. W-10 Holdings, Inc., holds a 50% interest in Washington 10
                Storage Partnership, a partnership that is developing and will
                operate the Washington 10 Storage Field, a 42 Bcf storage field
                in southeastern Michigan. Washington 10 Storage Partnership owns
                Washington 10 Storage Corporation.

             c. MCNIC Gas Storage Company, a subsidiary of MCNIC, sold its 25%
                interest in Blue Lake Gas Storage Company in December 1997.

             d. The Orchards Golf Limited Partnership, a Michigan partnership in
                which MCNIC Gas Storage Company has a 50% interest, developed,
                owns and operates a residential community and golf course on 520
                acres of land above the South Romeo gas storage field in
                southeastern Michigan.

        7.   MCNIC Power Company pursues domestic and international power
             generation related opportunities.

             a. CDC Ada, Inc., is a 99% limited partner in Ada Cogeneration 
                Limited Partnership, which owns and operates a 30 megawatt
                natural gas-fueled cogeneration facility in western
                Michigan.
        
             b. MCNIC Ada GP, Inc., was formed in 1996 and holds a 1% general
                partnership interest in the Ada Cogeneration Limited
                Partnership.

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        c.   Ludington Cogeneration Co. is the 1% general partner in Michigan
             Power L.P., a joint venture that built and operates a 123 megawatt
             natural gas-fueled cogeneration plant in western Michigan.

        d.   Ludington Cogeneration Holdings, Ltd. is a 49% limited partner in
             the 123 megawatt cogeneration plant mentioned above.

        e.   Summit Computing, Inc., a Delaware corporation, holds a
             99% limited partnership interest in Source Midland Limited
             Partnership. Source Midland Limited Partnership has an 18.125%
             general partnership interest in the Midland Cogeneration Venture
             Limited Partnership.

        f.   Source Cogeneration Company, a Delaware corporation, holds
             a 1% general partnership interest in Source Midland Limited
             Partnership.
 
        g.   Mobile Bay Energy, L.L.C. is constructing a 40 megawatt 
             cogeneration facility in Alabama (50% interest).

                                      Other
 

   8.   MCNIC International Holdings and MCNIC-GP International Holdings, each
        of Grand Cayman, Cayman Islands, hold a 99% and 1% interest,
        respectively, in IG-ONE LTD of Port-Louis, Mauritius. IG-ONE LTD. has a
        40 percent interest in Torrent Power Limited, a joint venture with
        Torrent Group of Ahmedabad, India. The joint venture will be involved in
        the electric generation and distribution business in western India. IG
        -ONE LTD. also holds ownership interests in other power generation
        projects in India.
 
   9.   MCNIC Nepal Limited holds a 65% ownership interest in a 36 megawatt
        hydroelectric power project in Nepal.

   10.  MCNIC Colombia Holdings was formed to be the shareholder of MCNIC
        Colombia International, which holds a 40% interest in an urea processing
        plant in Colombia.

   11.  Bridgewater Holdings, Inc. holds a limited partnership interest in 
        Bridgewater Place, a Grand Rapids, Michigan office building.
 
   12.  Combustion Concepts, Inc., holds patents for the development of
        pressurized combustion technologies which provide increased fuel
        efficiency, heat uniformity and compactness of equipment.

E. MCN MICHIGAN LIMITED PARTNERSHIP (MCN Michigan): MCN is the 1% general
   partner in MCN Michigan, a Michigan limited partnership. MCN Michigan exists
   for the sole purpose of issuing its limited partnership interests to the
   public in the form of preferred securities and investing the proceeds thereof
   in debt securities of MCN.
 
F. MCN FINANCING I: MCN is the sole owner of MCN Financing I, a Delaware
   Business Trust. MCN Financing I exists for the sole purpose of issuing
   preferred securities to the public and lending the gross proceeds thereof to
   MCN in exchange for MCN's Junior Subordinated Debentures.
 
G. MCN FINANCING II: MCN is the sole owner of MCN Financing II, a Delaware 
   Business Trust. MCN Financing II exists for the sole purpose of issuing      
   preferred securities and lending the gross proceeds thereof to MCN.
        

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H.    MCN FINANCING III: MCN is the sole owner of MCN Financing III, a Delaware
      Business Trust. MCN Financing III exists for the sole purpose of issuing
      preferred securities to the public and lending the gross proceeds thereof
      to MCN in exchange for MCN's Junior Subordinated Debentures.
        
I.    MCN FINANCING IV: MCN is the sole owner of MCN Financing IV, a Delaware
      Business Trust. MCN Financing IV exists for the sole purpose of issuing
      preferred securities and lending the gross proceeds thereof to MCN.
        
J.    MCN FINANCING V: MCN is the sole owner of MCN Financing V, a Delaware 
      Business Trust. MCN Financing V exists for the sole purpose of issuing 
      preferred securities and lending the gross proceeds thereof to MCN in 
      exchange for MCN's Junior Subordinated Debentures.
        
K.    MCN FINANCING VI: MCN is the sole owner of MCN Financing VI, a Delaware
      Business Trust. MCN Financing VI exists for the sole purpose of issuing
      preferred securities and lending the gross proceeds thereof to MCN in
      exchange for MCN's Junior Subordinated Debentures.
        
        



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