EXHIBIT 21-1 PENNSYLVANIA ENTERPRISES, INC. AND SUBSIDIARIES Subsidiaries of the Registrant The following are subsidiaries of the Registrant. Their voting securities are owned 100% by the Registrant. All of the subsidiaries are incorporated in Pennsylvania. PG Energy Inc. Pennsylvania Energy Resources, Inc. Theta Land Corporation Pennsylvania Energy Marketing Company Penn Gas Development Co.* Keystone Pipeline Services, Inc.** * A subsidiary of PG Energy Inc. accounted for on the equity method which has not been consolidated since it is insignificant. ** A subsidiary of Pennsylvania Energy Resources, Inc. ("PERI") included in the consolidation of PERI into the Registrant.