BY MiamiHerald.com

BY MICHAEL MARMESH

Special to The Miami Herald

''Form a line. Stay together. Don't stray from the group.'' A teacher addressing her class? No.

``And try not to exhale too many bubbles when they come close. It scares the hammerheads.''

These are directions from Patricia, our dive guide, given just before we back roll off the inflatable panga.''

My wife, Nancy, and I are scuba diving in the Galapagos Islands from the live-aboard dive boat Lammer Law. We are here to celebrate our 30th wedding anniversary.

In these islands there is as much to see beneath the water as there is above. We are shooting for a grand slam in underwater experiences -- swimming with sea lions, scalloped hammerheads, whale sharks and penguins.

No problem with finding sea lions. On the first day, we arrive on San Cristobal Island and the boat takes us into a cove for a checkout dive. There is no current here, but there are plenty of juvenile sea lions. While we're working on neutralizing our buoyancy, the kids come to play. They weave in and out, jetting at us, nipping at fins and hoses, and then veering off at the last second. We are enchanted.

Our next stop is Floreana Island. After diving in the morning, there's a land tour in the afternoon. Some divers come focused only on the diving and skip the shore excursions. Big mistake. Each live-aboard dive boat is required to have a trained naturalist on the crew. Thanks to Patricia, we see blue-footed boobies, more sea lions, green turtle nests, Sally Lightfoot crabs and a shallow lake with a resident flock of flamingoes.

One morning at about 60 feet down at Cousin's Rock, we approach what looks like a big dark cloud near the western point of the rock. Swimming beneath it we look up into a massive school of thousands of fish, selema, at least 50 feet across. Suddenly the school is scattered by three brown torpedoes -- sea lions, picking out their lunch from the bait ball. Wowsers!

In the afternoon the boat begins the 120-mile, 14-hour transit across the equator to the northern island of Wolf. The ride is a bit bouncy. For those predisposed to mal de mer, prevention is in order.

DIVING SHARK BAY

At 6:30 a.m., we dive Shark Bay and there they are -- the scalloped hammerheads. They swim in for cleaning by the local king angels, surgeonfish and barberfish. Patricia's right; they're scared of bubbles.

Next day we move 22 miles north, to Darwin Island. We are greeted by Darwin's Arch, a towering stone archway that looks like the last vestige of an ancient Atlantean civilization. We will spend three days here, diving and looking for ''the big guy,'' the whale shark. Largest fish in the sea at lengths of up to 60 feet, it is a harmless filter feeder.

Eight dives later we are out of luck. That's the nature of nature travel. You can't always get the animals to run on your schedule.

But we came oh so close on the last dive. One member of our group and the dive guide, Jaime, who were a little farther out in the blue, saw a shadow. They got close enough to view -- as they described it -- ``the bus go by.''

Still, the fifth dive at Darwin's Arch may have been our most outstanding dive ever. The scalloped hammerheads were coming in close, so we got a good look at the smaller fish cleaning them. Sex among hammerheads tends to be rough, with males biting the females for attention. Some of the girls had major scars that were being attended to.

After watching them for 15 minutes, the guide led the five of us out into the open blue to drift with the current. We were in an immense school of chub, little fish of 8 to 10 inches that seemed to ignore us.

Then in an instant they all took off downstream, forming a rosy, silver wall with each shimmering member of the school looking like a scale on the body of a giant fish. Everyone looked up current to see what had spooked them.

MAGIC MOMENT

On the decompression safety stop at 15 feet, the magic occurred. We were suddenly surrounded by an enormous pod of dolphins. Most just went tooling by, but a few cruised in to give us a closer look. There were well over a hundred of them. Wooooo-ey.

Amazingly there was one more little bonus -- a Galapagos sleigh ride. Just as we finished sloshing back aboard the panga, the driver pointed and yelled, ''Orca!'' Actually two, a mother and a calf. We spent the next half-hour following them and watching them breach and spout.

KEEPING THE FAITH

A word about the difficulty level of the diving is probably in order. Scuba here is not for the beginner. A full 5mm wetsuit or drysuit and experience dealing with currents are absolute musts.

Panga diving is faith-based diving. The panga, an 18-foot RIB (rigid, inflatable boat), leaves the mother ship and ferries the divers to the site. At the dive guide's signal, all divers roll backward over the side and meet down on the reef.

Half an hour to an hour later, when you surface, you have faith that the panga driver will see you and pick you up. On one strong current dive, this meant dropping in at one side of the arch and getting picked up on the opposite side. Even with five-foot swells, the driver was right there. These guys are good.

At Punta Vicente Roca, we finally saw a single penguin. Galapagos penguins are the second smallest species behind fairy penguins. There was one little fella standing on shore two feet above the waterline. He dove in as our panga approached. He would be the only penguin we saw.

On the west side of Isabela Island, the flora and fauna underwater were quite different. This side is bathed by the Cromwell Current, one of the four major ocean currents that converge in the archipelago and give it such a diversity of sub aquatic climates. Here we met the bizarre mola mola, or ocean sunfish. Largest of the bony fishes, ours was a four-foot diameter silver disk with long, thin dorsal and pectoral fins, essentially no tail and a beak-like mouth.

But not all our dives were great. The next one, at exactly the same site, was like swimming in a bowl of pea soup 50 feet deep. The only animals we saw were a green turtle and a curious lone sea lion that came close trying to figure out why we were there.

Our last two dives were at Cabo Marshall. On the first we were greeted by a large, cruising manta, 10 feet across. Then we ran into another large group of juvenile sea lions, exuberant as kids on the last day of school. They performed loop-the-loops and figure eights, buzzing each other just for the sheer joy of it. Two even harassed a four-foot white tip shark. They checked us out, stopping two feet from our masks, their enormous round eyes staring at us, then zipped off.

The last dive was a slow, meditating drift at six or seven fathoms. We spotted blue starfish and rays sleeping on ledges as we floated by, thinking about what we'd seen and what we'd missed.

As we surfaced for the last time, we came through a school of noncommittal chubs, then a school of standoff-ish 10-pound argent snapper, and finally maybe a thousand curious Pacific barracudas. Unlike the hulking, silver Atlantic giants with bad orthodontia, these are cute little two-foot guys with horizontal yellow pinstripes.

Did we complete our grand slam? No, we were only a little more than half successful. If you go will you see everything we saw? Highly unlikely. You're sure to miss some, but you're also going to see things we didn't.

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