The Interior Department has proposed a regulation that will complicate -- and in some case limit -- the collection of rocks and fossils on some federal lands.

The rule has pleased officials of the Smithsonian Insitution's Museum of Natural History and a large association of geologists, but has angered commercial collectors and some scientists.

The mixed reaction reflects a growing internal squabble for prospecting rights among the professional and amateur devotees of the natural history buried in Earth's crust.

Comments are due a week from today on the Bureau of Land Management proposal to require commercial collectors to get permits if they want to pull the fossilized remains of trees, plants, fish and mammals out of the bureau's vast tracts of land in the West and Midwest.

Under the proposal, those who collect rocks or fossils as a hobby would be limited to 25 pounds of rocks daily and 250 pounds annually. One commercial fossil and mineral collector estimated there are 2 million amateur rock collectors in local hobby organizations around the country.

Geologists and paleontologists could apply -- and pay a $25 fee -- for a scientific free use permit that allows more extensive excavation for scientific purposes.

But neither scientific nor hobby collectors may sell the mineral or fossil specimens they find.

James Mello, deputy director of the Museum of Natural History, said that, if anything, the rules do not go far enough.

"Fossils are becoming a rather lucrative business," he said. "Because so many people are amateurs or don't give a damn they could go in and destroy a lot to get a little."

A.G. Unklesbay, executive director of the American Geological Institute, said, "I think it's necessary to have some control. I've been to places where one person comes in and takes everything that's good and puts it up for sale -- that's not fair . . . That's the reason BLM had to put the rules in."

But Peter Larson, an official of the Black Hills Institute, a commercial fossil and minerals business, said delays and restrictions resulting from the rule will destroy more fossils than they will save.

"What the people who wrote these rules don't understand is that the fossils are weathering out each year," Larson said. "It's like a farmer's crop -- to save it you have to harvest it. One rain will wash a fossil into view and the next will destroy it."