Yes, even dogs can get heat stroke.

A Seeing Eye dog named Elmo collapsed in the middle of a three-hour Circle Line tour in the early evening on Monday, when temperatures topped 90 degrees. But executives of the ferry service had a car waiting to rush him to a veterinary hospital when he was carried off the boat after it docked.

“He was actually comatose when he was brought in, so the actions of the staff and the passengers saved Elmo’s life, without a doubt,” said Bonni S. Voiland, a spokeswoman for NYC Veterinary Specialists, the Midtown hospital where Elmo was treated.

As of Tuesday morning, Elmo — a 6-year-old Labrador retriever — was awake and wagging his tail, though he has not fully recovered, said Ms. Voiland. “All of his lab work is not normal yet. We’re waiting for that to happen.” She added: “Heat stroke is a very serious thing. We’re keeping him today and tomorrow.”

Almost all mammals can suffer heat stroke. Unlike humans, dogs do not sweat through their skin. Instead they

sweat through their foot pads and nose. In addition, they release heat primarily by panting. Animal experts provide an abundance of advice for taking care of pets in the summer, including not leaving them in the car.

Elmo’s owner is Neva Fairchild, a visually impaired woman from Texas who was vacationing in New York. She was in the region for the celebration of the 80th anniversary for the Seeing Eye, the guide-dog school in Morristown, N.J., where Elmo was trained.

Ms. Fairchild took the Circle Line trip with her daughter and Elmo. Elmo collapsed almost exactly halfway through the tour, so it did not make sense for the boat to turn back, officials said.

On land, Andreas Sappok, the general manager for Circle Line, learned of the situation and tried calling 911. The emergency operators said they could not respond to a nonhuman emergency, and referred Mr. Sappok to the city’s 311 hotline, he said. Operators there referred him to 411, directory assistnce.

Finally, Mr. Sappok reached the Veterinary Specialists, which is located at West 55th between Ninth and Tenth Avenues.

The ferry sped through the remainder of the trip. The crew was instructed to remove Elmo from the heat, wrap him in cold towels and put ice on his neck to reduce the strain.

Mr. Sappok arranged for the company car to wait for Elmo when he was carried off the boat in a stretcher around 7 p.m. The pet hospital was located only a short distance from where the Circle Line docks. “After he left the water, five minutes later he was in the hospital,” said Mr. Sappok.

Circle Line, which has been around for 65 years, has had its own share of medical human emergencies — including heart attacks and fainting.

“If you carry over a million people a year, there is always something happening,” Mr. Sappok said.