To shoppers browsing in Midtown Manhattan, the objects might have resembled curios brought home by globe-trotters of a bygone age: bone-white carvings fashioned into jewelry, animal figurines and other gifts.

But in reality, they were made of ivory from the tusks of Asian and African elephants killed by poachers, the authorities said.

Following one of the largest seizures of illicit ivory sold in New York, two jewelers and their stores pleaded guilty on Thursday to marketing what prosecutors said was more than $2 million worth of the goods.

“We’re here today because poachers of endangered species, who profit from wildlife crime, should not have a market in Manhattan,” the Manhattan district attorney, Cyrus R. Vance Jr., said at a news conference.