The Boston Landmarks Commission this week deferred a decision on whether to block plans of the Harvard-affiliated Massachusetts General Hospital (MGH) which call for demolishing its 90-year-old Resident Physicians House and replacing it with a 10-story research lab.

The commission postponed for two weeks a final ruling on the landmark status of the Physicians' House, located on Blossom St. in MGH's Boston complex.

MGH officials hope to use a $60-million grant for the construction of a research building in genetics on the Blossom St. site. The donation offered by a German chemical company stipulated that the building be completed before April 1, 1982.

Roger Snow, a Beacon Hill resident who organized a petition requesting that the commission grant the landmark status and thereby prevent the demolition or alteration of the building's exterior, said yesterday that the house--currently used for MGH offices--is of both architectural and historic significance, but that its architect, Carl Fehmer, "hasn't gotten much recognition" for several buildings he designed in downtown Boston.

Herbert P. Gleason '50, the attorney representing MGH, said that "the house is really not of landmark importance." A study done by the hospital found that the house is "simply not notable," Gleason added.

Snow said landmark status is difficult to get, as six of the nine members on the commission must vote in favor of the special designation in order for it to pass. But he added that he is "cautiously optimistic."