With tides short, the crew leaves San Lucas for Pulmo Reef. Approaching shallow green water, Tony posts a lookout in the crow’s nest to spot rocks and anchors near the reef. A canoe from a small rancheria comes alongside. The ragged men and a woman cover their mouths with greasy blankets “to protect themselves” (63). They linger silently until one offers a matchbox of misshapen pearls; the crew trades cigarettes and the visitors paddle away. The skiff is loaded with bars, jars, tubes, and buckets. The Sea-Cow starts up and actually works for a short while, before quitting when it becomes “aware of its mistake” (64), so they row to the reef.

Wearing boots for stinging organisms, they collect widely on the coral: Gorgonians, cushion stars, puffer fish, barnacles, brittle-stars, oysters, limpets, sponges, corals, peanut worms, sea cucumbers, many crabs, and the stinging worm Eurythoë. Sharp urchin spines pierce toes. One diver retrieves a single large sea-fan from under the reef. Pieces of coral are kept in pans so hidden residents emerge as the water goes stale. Behind the reef, warm water invites diving for perfect coral knobs in tennis shoes.

Back aboard, Tex disassembles the Sea-Cow and discovers it will “run perfectly out of water” (67) but fails whenever they actually need it. Underway again, the crew preserves and labels an extensive haul, already short on small containers. Mirages along the coast distort headlands; trolling yields a skipjack, but attempts to take photographs fail. Swordfish and manta rays appear; a light harpoon only grazes a tail. Rising wind forces a shift to shelter at Pescadero Point, where they anchor and cook the skipjack. After dinner, Tex’s aversion to washing dishes causes an intervention. When the dirty dishes are dumped in his bunk, he finally accepts that he must do his part to wash the dishes. The night is “quiet and strange” (75) at anchor, with the crew reading and listening to fishermen on the radio.

At dawn, the Western Flyer crosses from Pescadero Point to the southern end of Espíritu Santo Island, its exposed shore contrasting with sheltered La Paz. Manta rays appear at the surface and two yellowfin tuna hit the trolling lines. The crew anchors off a bouldery beach and everyone but Tony goes ashore to collect specimens. The shore teems with life: Sulfur-dusted sea cucumbers dominate, with giant brittle-stars a close second. They also find multiple starfish and urchins (including the sharp, poisonous Centrechinus mexicanus), many crabs and shrimps, anemones, worms (the stinging Eurythoë), chitons, limpets, clams, flatworms, sponges, bryozoans, and snails. Back aboard, a sea cucumber yields a pale commensal fish that repeatedly darts in and out of its anus. With holds filling, they decide to preserve enough of the common cucumbers and brittle-stars and thereafter just note occurrences.

After Sparky cooks the tuna, two Indigenous persons from a nearby ranchería visit in a plaster-coated dugout canoe. Once fortified with Sparky and Tiny’s over-strong wine, they grow talkative and depart with prized empty tins. Eager for La Paz but avoiding night pilot fees, the Flyer anchors off Prieta Point until daylight, then is guided by a pilot through the winding channel to a berth off town. Officials board and assign courteous armed guards to the ship, then an agent begins provisioning while the crew goes ashore. They return laden with curios.

On the warm, flat shallows east of town, the party collects a new suite of lagoon species: Ghost shrimps in burrows, decorated crabs, purple polyclad worms, hacha oysters, corals, nudibranchs, mantis shrimps, sipunculids, and more. Local boys discover that they can be paid per specimen and swarm the boat with finds. One ambitious fixer overreaches and is beaten by rivals. Another boy timidly asks for “cinco centavos” (95) and Steinbeck imagines his bullying father at home. They give him a peso before pushing off, prices in town already nudging upward once boatmen learned the Sea-Cow would not run.

On Good Friday in La Paz, the crew cleans up and attends church, where a children’s choir sings the Stations of the Cross and a fervent young priest delivers a stirring sermon. Afterward, they wander the quiet streets. Seeking provisions, they purchase two chickens; a chaotic yard chase draws half the neighborhood before the birds are caught. Sparky kills and stews them, but the “gallant, fast chickens” (99) prove inedible.

That afternoon, they cross to the broad tidal flats of El Mogote with Raúl Velez, a helpful local youth with a canoe who shares regional names for marine life. On the warm, shallow sands, they collect two species of Dentalium, several small anemones and sand anemones, multiple sea cucumbers (including small black forms and a pepper-and-salt type), heart urchins, common and burrowing brittle stars, sponges, tunicates, flatworms, stinging and peanut worms, an echiurid, and a striking white sea-whip colony. Working up toward the mangroves, they note the foul smell and heavy life among the roots, including large hermit crabs, then take barnacles from a wreck lying on the flat.

They buy Raúl’s iron harpoon (later to be lost in a manta) but cannot purchase a prized Nayarit canoe. At dusk, they return to find the deck crowded with boys selling specimens; their courteous armed guard manages the crowd and quietly shames a boy who attempts to deceive. A boy presents a botete fish, known locally as poisonous and used to kill cats; they acquire specimens and note its prevalence in the shallows. Tiny reboards with specimens of pubic lice. That night, they stroll La Paz once more, then sit on deck listening to the tide and the distant barking of dogs as the trading boat is pumped for departure.

They depart from La Paz in the morning with the pilot guiding them out, then head north toward San José Island and anchor at Amortajada Bay. Drawn to the small dark islet Cayo, they row over when the Sea-Cow again refuses to run. Around Cayo, they find no landing place and see large iron rings and “very old” (107) chains set in boulders and in the cliff, plus shallow caves with fire sites piled with clam and turtle shells and even fresh diced turtle meat, despite there being no clams, wood, water, or safe anchorage on the islet.

They climb to the flat top, note sparse grass, cactus, and a single black crow, and then collect a scant fauna: Small pale Heliaster sun-stars, a few anemones, sea cucumbers, sea rabbits, Aletes snails, serpulid worms, several other snails, isopods, and beach-hoppers, with lots of Sally Lightfoot crabs. As the tide threatens the skiff they row back, cursing the Sea-Cow. Tex fully dismantles the Sea-Cow under a deck light, reassembles it, and proves it will run by taking a short trip.

That night, anchored near San José, the crew is plagued by biting black beetle-like flies; unable to sleep, they talk while Tiny recounts “decoratively disreputable sagas” (108) from his past.

The crew reaches a “hot and yellow” (109) beach and swims. They walk along the sand and then inland on a ridge that separates the beach from a mangrove lagoon. The lagoon side shows thousands of burrows that likely belong to large land crabs. The shores hold clicking fiddler crabs and estuarine snails. The mangrove flowers give a fresh grassy odor without the foul scent of roots. The water lies still and reflects the green mangroves and the red brown mountains. Occasionally, a lagoon fish breaks the surface. Collecting is light and unhurried. They rest and talk.

The setting is quiet, so Steinbeck begins to reflect on “teleological notions” (112). Informed by the thinking of Ed Rickeets, he sets out the contrast between “cause effect thinking” and what they call “non teleological” thinking. Steinbeck links this method to observation in the field. He frames events as expressions rather than as results, asking what and how rather than why. Concrete examples support the method. Economic want during the Depression, Steinbeck suggests, illustrates statistical realities of employment. The sea hare Tethys, which produces hundreds of millions of eggs, illustrates extreme variance and selection. Variation in human height and in the length of matches shows the universality of deviation around a mean. A note on leadership compares mass movement to the flow of an ameba into its pseudopod.

Steinbeck relates micro level freedom and macro level pattern. He remarks on quanta, on the constancy of the speed of light, and on the persistence of residual anomalies. He holds that a full picture must include errors and beliefs in proportion to their spread. He presents non teleological thinking as a modus operandi that can extend from thinking to living.

As evening comes, Steinbeck notes that collecting, eating, sleeping, and talking merge with the sea, the light, and the engine into one perceived whole, the “deepest word of deep ultimate reality” (125).

The crew leaves Amortajada Bay at noon and heads north along the coast to Marcial Reef near Marcial Point, the southern limit of Agua Verde Bay. They arrive in mid-afternoon and work the late tide on a northern boulder pile of the central reef. The water does not fall as predicted, so access is limited. They note a few polyclads high on the rocks. They take two large and many small chitons. Many urchins sit beyond reach below the surface. Clouds of larval shrimps circle in the shallows. The station yields few forms.

After dark, they hang a shaded lamp close to the water and use dip nets and porcelain pans. Pelagic isopods and mysids swarm into the light. Small fish move into the circle and larger fish flash at the edge. Before dawn they return to the reef with seven cell focusing flashlights. The narrowed beam improves detail and shows nocturnal activity. They lift a large blue and orange spiny lobster from a crevice without struggle. The cavities hold many club-spined urchins and sharp-spined purple urchins. Two familiar starfish are found with a third species that will prove common farther north. They collect many rayed sun stars and a flat sea cucumber that is new to them. Puffer fish feed near the surface. Brittle stars move openly across the bottom.

Back aboard, they record chitons, tunicates, turbellarian flatworms that resist preservation, brittle stars, small crabs, snapping shrimps, plumularian hydroids, bivalves, snails, small urchins, worms, hermit crabs, sipunculids, sponges, and heavy numbers of pelagic larvae. The crew remarks on the density of small pelagic animals in the warm, shallow water. They raise anchor and continue north. Lines on the stays bring in skipjack and sierra. The sierra is golden with blue spots, swims fast, and provides firm white meat that fries well. A light harpoon remains ready at the bow for swordfish, but attempts fall short and no strike lands. The routine of running to a station, collecting, preserving, and moving on fixes into habit.